Patent Publication Number: US-11032073-B2

Title: Seamless abort and reinstatement of TLS sessions

Description:
BACKGROUND 
     The present disclosure relates to the field of network security, and particularly network security that involves cryptography. Still more particularly, the present invention relates to encryption sessions and the management thereof. 
     SUMMARY 
     A method, system, and/or computer program product maintains a seamless Transport Layer Security (TLS) communication connection between a client and a server. A Man in the Middle (MitM) computer receives a first session identifier from a client for a first communication session between the client and a server, wherein the MitM computer monitors Transport Layer Security (TLS) communication sessions between the client and the server, and wherein the first session identifier is one of an unknown session identifier that is not recognizable by the MitM computer and an invalid session identifier. In response to receiving the first session identifier from the client for the first communication session between the client and the server, the MitM computer performs one of: requesting a second session identifier from the server for a second communication session between the server and the MitM computer if the first session identifier is an unknown session identifier; and transmitting, to the client, an instruction to flush a session cache in the client, wherein flushing the session cache in the client forces the client and the server to establish a full TLS handshake in order to obtain a session key if the first session identifier is an invalid session identifier. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  depicts an exemplary system and network in which the present disclosure may be implemented; 
         FIG. 2  illustrates various Man in the Middle (MitM) processes for managing Transport Layer Security (TLS) sessions; 
         FIG. 3  is a flow chart of one or more steps performed by one or more processors to seamlessly abort an existing Transport Layer Security (TLS) session in accordance with one or more embodiments of the present invention; 
         FIG. 4  is a high-level flow chart of one or more steps performed by one or more processors to seamlessly abort an existing Transport Layer Security (TLS) session in accordance with one or more embodiments of the present invention; 
         FIG. 5  depicts a cloud computing environment according to an embodiment of the present invention; and 
         FIG. 6  depicts abstraction model layers of a cloud computer environment according to an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     The present invention may be a system, a method, and/or a computer program product. The computer program product may include a computer readable storage medium (or media) having computer readable program instructions thereon for causing a processor to carry out aspects of the present invention. 
     The computer readable storage medium can be a tangible device that can retain and store instructions for use by an instruction execution device. The computer readable storage medium may be, for example, but is not limited to, an electronic storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the foregoing. A non-exhaustive list of more specific examples of the computer readable storage medium includes the following: a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), a static random access memory (SRAM), a portable compact disc read-only memory (CD-ROM), a digital versatile disk (DVD), a memory stick, a floppy disk, a mechanically encoded device such as punch-cards or raised structures in a groove having instructions recorded thereon, and any suitable combination of the foregoing. A computer readable storage medium, as used herein, is not to be construed as being transitory signals per se, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through a waveguide or other transmission media (e.g., light pulses passing through a fiber-optic cable), or electrical signals transmitted through a wire. 
     Computer readable program instructions described herein can be downloaded to respective computing/processing devices from a computer readable storage medium or to an external computer or external storage device via a network, for example, the Internet, a local area network, a wide area network and/or a wireless network. The network may comprise copper transmission cables, optical transmission fibers, wireless transmission, routers, firewalls, switches, gateway computers and/or edge servers. A network adapter card or network interface in each computing/processing device receives computer readable program instructions from the network and forwards the computer readable program instructions for storage in a computer readable storage medium within the respective computing/processing device. 
     Computer readable program instructions for carrying out operations of the present invention may be assembler instructions, instruction-set-architecture (ISA) instructions, machine instructions, machine dependent instructions, microcode, firmware instructions, state-setting data, or either source code or object code written in any combination of one or more programming languages, including an object oriented programming language such as Java, Smalltalk, C++ or the like, and conventional procedural programming languages, such as the “C” programming language or similar programming languages. The computer readable program instructions may execute entirely on the user&#39;s computer, partly on the user&#39;s computer, as a stand-alone software package, partly on the user&#39;s computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer may be connected to the user&#39;s computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection may be made to an external computer (for example, through the Internet using an Internet Service Provider). In some embodiments, electronic circuitry including, for example, programmable logic circuitry, field-programmable gate arrays (FPGA), or programmable logic arrays (PLA) may execute the computer readable program instructions by utilizing state information of the computer readable program instructions to personalize the electronic circuitry, in order to perform aspects of the present invention. 
     Aspects of the present invention are described herein with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and/or block diagrams, and combinations of blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer readable program instructions. 
     These computer readable program instructions may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks. These computer readable program instructions may also be stored in a computer readable storage medium that can direct a computer, a programmable data processing apparatus, and/or other devices to function in a particular manner, such that the computer readable storage medium having instructions stored therein comprises an article of manufacture including instructions which implement aspects of the function/act specified in the flowchart and/or block diagram block or blocks. 
     The computer readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, other programmable apparatus or other device to produce a computer implemented process, such that the instructions which execute on the computer, other programmable apparatus, or other device implement the functions/acts specified in the flowchart and/or block diagram block or blocks. 
     The flowchart and block diagrams in the Figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present invention. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of instructions, which comprises one or more executable instructions for implementing the specified logical function(s). In some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems that perform the specified functions or acts or carry out combinations of special purpose hardware and computer instructions. 
     With reference now to the figures, and in particular to  FIG. 1 , there is depicted a block diagram of an exemplary system and network that may be utilized by and/or in the implementation of the present invention. Some or all of the exemplary architecture, including both depicted hardware and software, shown for and within computer  101  may be utilized by software deploying server  149  and/or server  151  and/or client  153  shown in  FIG. 1 . 
     Exemplary computer  101  includes a processor  103  that is coupled to a system bus  105 . Processor  103  may utilize one or more processors, each of which has one or more processor cores. A video adapter  107 , which drives/supports a display  109  (which in one or more embodiments of the present invention is a touch-screen display capable of detecting touch inputs onto the display  109 ), is also coupled to system bus  105 . System bus  105  is coupled via a bus bridge  111  to an input/output (I/O) bus  113 . An I/O interface  115  is coupled to I/O bus  113 . I/O interface  115  affords communication with various I/O devices, including a keyboard  117 , a mouse  119 , a media tray  121  (which may include storage devices such as CD-ROM drives, multi-media interfaces, etc.), and external USB port(s)  125 . While the format of the ports connected to I/O interface  115  may be any known to those skilled in the art of computer architecture, in one embodiment some or all of these ports are universal serial bus (USB) ports. 
     As depicted, computer  101  is able to communicate with a software deploying server  149  and/or other devices/systems (e.g., server  151  and/or client  153 ) using a network interface  129 . Network interface  129  is a hardware network interface, such as a network interface card (NIC), etc. Network  127  may be an external network such as the Internet, or an internal network such as an Ethernet or a virtual private network (VPN). In one or more embodiments, network  127  is a wireless network, such as a Wi-Fi network, a cellular network, etc. 
     A hard drive interface  131  is also coupled to system bus  105 . Hard drive interface  131  interfaces with a hard drive  133 . In one embodiment, hard drive  133  populates a system memory  135 , which is also coupled to system bus  105 . System memory is defined as a lowest level of volatile memory in computer  101 . This volatile memory includes additional higher levels of volatile memory (not shown), including, but not limited to, cache memory, registers and buffers. Data that populates system memory  135  includes computer  101 &#39;s operating system (OS)  137  and application programs  143 . 
     OS  137  includes a shell  139 , for providing transparent user access to resources such as application programs  143 . Generally, shell  139  is a program that provides an interpreter and an interface between the user and the operating system. More specifically, shell  139  executes commands that are entered into a command line user interface or from a file. Thus, shell  139 , also called a command processor, is generally the highest level of the operating system software hierarchy and serves as a command interpreter. The shell provides a system prompt, interprets commands entered by keyboard, mouse, or other user input media, and sends the interpreted command(s) to the appropriate lower levels of the operating system (e.g., a kernel  141 ) for processing. While shell  139  is a text-based, line-oriented user interface, the present invention will equally well support other user interface modes, such as graphical, voice, gestural, etc. 
     As depicted, OS  137  also includes kernel  141 , which includes lower levels of functionality for OS  137 , including providing essential services required by other parts of OS  137  and application programs  143 , including memory management, process and task management, disk management, and mouse and keyboard management. 
     Application programs  143  include a renderer, shown in exemplary manner as a browser  145 . Browser  145  includes program modules and instructions enabling a world wide web (WWW) client (i.e., computer  101 ) to send and receive network messages to the Internet using hypertext transfer protocol (HTTP) messaging, thus enabling communication with software deploying server  149  and other systems. 
     Application programs  143  in computer  101 &#39;s system memory (as well as software deploying server  149 &#39;s system memory) also include Logic for Managing Transport Layer Security Sessions (LMTLSS)  147 . LMTLSS  147  includes code for implementing the processes described below, including those described in  FIGS. 2-4 . In one embodiment, computer  101  is able to download LMTLSS  147  from software deploying server  149 , including in an on-demand basis, wherein the code in LMTLSS  147  is not downloaded until needed for execution. In one embodiment of the present invention, software deploying server  149  performs all of the functions associated with the present invention (including execution of LMTLSS  147 ), thus freeing computer  101  from having to use its own internal computing resources to execute LMTLSS  147 . 
     The hardware elements depicted in computer  101  are not intended to be exhaustive, but rather are representative to highlight essential components required by the present invention. For instance, computer  101  may include alternate memory storage devices such as magnetic cassettes, digital versatile disks (DVDs), Bernoulli cartridges, and the like. These and other variations are intended to be within the spirit and scope of the present invention. 
     Transport Layer Security (TLS) is a cryptographic protocol that provides communications security over a computer network, including a network that provides communication between a server (e.g., server  151  shown in  FIG. 1 ) and a client (e.g., client  153  shown in  FIG. 1 ). TLS may provide cryptographic protection while a client and server communicate in the course of utilizing applications such as web browsers, email applications, Internet sessions (e.g., Voice over an Internet Protocol session—VoIP, Internet facsimile transmissions, etc.) 
     TLS provides security, privacy, and data integrity during a communication session between two communicating computer applications. For example, when the communication session is between a client (e.g., a web browser) and a server (e.g., a webpage server), TLS provides symmetric cryptography to encrypt the data transmitted. The keys for the symmetric encryption are generated uniquely and specifically for each communication session (i.e., “connection”) and are shared between the client and the server at the start of the communication session using a TLS handshake before the first byte of data is transmitted between the client and the server. 
     A TLS handshake (as well as a Secure Socket Layer—SSL handshake) enables a TLS client and server to establish the secret keys with which they communicate. During the SSL/TLS handshake, the client and server 1) agree on the version of the protocol to use (SSL or TLS); 2) select cryptographic algorithms; 3) authenticate each other by exchanging and validating digital certificates; and 4) use asymmetric encryption techniques to generate a shared secret key, which avoids the key distribution problem. SSL/TLS then uses the shared key for the symmetric encryption of messages, which is faster than asymmetric encryption. 
     If the TLS session (i.e., the encrypted data transmission between the client and the computer) is interrupted (i.e., the encryption is interrupted, thus causing the communication session to be aborted), the present invention enables the TLS session to be reinstated using a TLS session resumption that speeds up (and/or eliminates) a TLS handshake, thus reducing computing overhead. This TLS session resumption process utilizes an intermediary system known at the “Inspector” (i.e., computer  101  shown in  FIG. 1 ), which maintains a copy of the TLS encryption related information needed to re-establish the TLS session, such as session identifiers, encryption keys, etc. in a TLS communication session between a client (e.g., client  153  shown in  FIG. 1 ) and a server (e.g., server  151  shown in  FIG. 1 ). 
     When performing TLS traffic inspection, the private key used in the TLS session is imported by the inspector to intercept the TLS connection. However, the inspector must detect the full TLS handshake in order to obtain the session key. When performing TLS session resumption, the client and server use a pre-negotiated session key to encrypt the payload, which causes security issues if the inspector does not know the pre-negotiated keys, since services and systems that support TLS session resumption have a precondition of requiring to see the very first TLS handshake sequence in order to obtain the session key. This causes various problems in the prior art. 
     First, there are thousands of ongoing TLS sessions in a production environment. This requires the TLS management service/system (i.e., the hardware and software that provides the functionality of the “inspector” described herein) to wait until all of the TLS sessions expire before the inspector can see the complete TLS handshake. This requires a session timeout that may be between 3 hours and 12 hours in many situations, which means that the TLS management system cannot inspect the TLS connection until this time period expires. Furthermore, during this waiting period, the network is unprotected while the TLS operations are incomplete (i.e., are in progress). 
     Second, the TLS management service/system may be restarted/reloaded many times. This may results in the loss of stored session keys, thereby forcing the TLS management system to wait for the old TLS session to expire before inspecting the new TLS connection, which requires another 3 hours to 12 hours or longer. 
     Third, such TLS management services/systems afford poor scaling and availability capability when TLS session resumption occurs, since the system needs to keep the TLS session keys in order to inspect the future resumed TLS traffic. However, there is no guarantee that one TLS connection will always be inspected by the same TLS management system. For example, a load balancer might distribute the same TLS connect to different TLS management services/systems due to availability and/or or scaling concerns. The second TLS management service/system then needs to wait for the old session to expire before starting the inspection of the TLS connection. 
     Fourth, such TLS management services/systems provide poor support to roaming users. For example, when a user switches from a cellular network to an intranet, most of the TLS connections on his/her devices have existing sessions. Therefore, it is impossible for a single TLS management system/service to inspect the traffic from the roaming user promptly, which results in a security breach. 
     Thus, in the prior art, there is currently no way to effectively intercept existing TLS connections without breaking the connections themselves. 
     Therefore, one or more embodiments of the present invention address the problems just stated by providing an inspector (e.g., computer  101  shown in  FIG. 1 ), which acts as a Man in the Middle (MitM) computer for certain connections (e.g., between client  153  and server  151  shown in  FIG. 1 ). This allows the inspector to drop session identifiers (session ID or ticket) not recognizable and to create new sessions immediately without dropping connections. Once the inspector receives an unknown session identifier from the client, it ignores the unknown session identifier and requests the server to issue a new one, either by sending another random identifier to the server or by not sending another random identifier to server. In either scenario, the server (e.g., server  151  shown in  FIG. 1 ) will reply to the inspector (e.g., running on computer  101  shown in  FIG. 1 ) with the new session identifier. However, the inspector (i.e., the MitM computer) does not send the new session identifier to the client (e.g., client  153  shown in  FIG. 1 ). Rather, the session identifier sent to client is either a session identifier generated by the inspector, or else the inspector sends an empty (e.g., “null”) session identifier to the client. 
     Since the inspector obtained the session keys for both sides (i.e., between the inspector and the server and between the inspector and the client), the connection between the server and the client (via the MitM inspector) is decrypted and re-encrypted by the MitM inspector for the current connection/session. Once the current connection/session expires, the client will attempt to establish a next connection/session. However, the client will be unable to provide a valid session identifier, since this was wiped at the end of the prior connection/session. Thus, the next connection/session requires a full handshake to be then performed, thus allowing the inspector to inspect this connection passively (e.g., to perform decryption of traffic between the client and the server). 
     With key syncing, the present invention can forward a session identifier intact when a new session identifier is received from the server, thus allowing the next connection to be passively inspected by the inspector. 
     Thus, one or more embodiments of the present invention enhance session/communication protection effectiveness while not breaking the endpoint experience. 
     At a high level view, one or more embodiments of the present invention include two steps: 1) Drop an unknown session identifier by the MitM computer, and 2) retrieve a session identifier. 
     1. Drop Unknown Session Identifier by the MitM Computer 
     With reference now to  FIG. 2 , consider session identifier flow  202 . For every TLS connection initiated between a client and a computer, the inspector first checks a lookup table to determine whether the session identifier exists in it. Once the inspector detects an unknown session identifier A when an inbound TLS connection is initiated, the inspector will remove the session identifier from a handshake message to the server, thus forcing the server to start a full handshake, which will return a new session identifier B to the inspector. Whether key syncing is enabled will determine whether an extra step is needed. 
     That is, in session identifier flow  202 , assume that there is no key syncing. As shown in session identifier flow  202 , the inspector returns no session identifier to the remote client. When a new connection is established between this client and the server, we go to step 2 (see below: 2) retrieve a session identifier), where the server will have to generate a new session identifier before resumption actually occurs. 
     As shown in session identifier flow  204 , assume now that there is key syncing. As shown in session identifier flow  204 , this key syncing allows the inspector to return the session identifier B to the client. 
     2. Retrieve Session Identifier 
     With respect to session identifier flow  206  in  FIG. 2 , assume again that key syncing is not available. Since the inspector has told the client not to store the session by not issuing a valid session identifier, once the client initiates a new TLS connection, the inspector falls back to passive mode (just monitoring the TLS session), thereby obtaining any future session identifiers (i.e., session identifier C) for inspection and use (e.g., to decrypt TLS traffic between the client and the server). 
     With reference now to  FIG. 3 , a flow chart of one or more steps performed by one or more processors to seamlessly abort and then reestablish an existing Transport Layer Security (TLS) session in accordance with one or more embodiments of the present invention is presented. After initiator block  301 , the Man in the Middle (MitM) computer (i.e., “inspector”, such as computer  101  shown in  FIG. 1 ) receives a handshake message from a client (e.g., client  153  shown in  FIG. 1 ), as described in block  303 . 
     As described in block  305 , the MitM computer looks for the session identifier (found in the handshake message from the client) in a database. If the session identifier is found (query block  307 ), then the handshake is forwarded to the server (block  309 ) and the inspector receives a handshake message from the server (block  311 ). If the server is not accepting a resumption of the TLS session (query block  313 ), then the session cache in the database is updated (block  315 ) and the inspector monitors for a full handshake between the client and server (block  317 ). 
     However, if the server is accepting resumption of the TLS session (query block  313 ), then a determination is made as to whether the server has issued a new session identifier (query block  319 ). If so, then the session cache is updated using the new session identifier from the server (block  321 ). 
     The abbreviated handshake between the client and the server is then monitored (block  323 ), and the inspector passively monitors the TLS session between the client and the server (block  325 ). 
     Returning to query block  307 , if no session identifier is found in the database, then the inspection fails (block  329 ), and the process may end (terminator block  327 ). However, in one or more embodiments of the present invention, this failure results in the process depicted in blocks  331 - 345 . 
     That is, in block  331 , the inspector intercepts the next (new) TLS communication session being requested by the client. The inspector sends a new handshake message to the server, with or without a session identifier (block  333 ). The server responds with a handshake message (block  335 ). That is, the inspector either responds to the handshake message by sending a message to the client without a session identifier (block  337 ) or with a session identifier (block  339 ). In either scenario, the session cache is updated in the inspection computer&#39;s session cache using the new session identifier (block  341 ). 
     However, when the client attempts to establish a subsequent (next) TLS session, it no longer has a valid session identifier. This forces the client to do a full handshake with the server (block  343 ). Thereafter, the MitM computer/inspector is able to decrypt and re-encrypt data in the new TLS session by retrieving, from the TLS session that resulted from the full handshake, the requisite key (block  345 ). 
     The flow-chart ends at terminator block  327 . 
     With reference now to  FIG. 4 , a high-level flow chart of one or more steps performed by one or more processors to seamlessly abort an existing Transport Layer Security (TLS) session in accordance with one or more embodiments of the present invention is presented. 
     After initiator block  402 , a Man in the Middle (MitM) computer (e.g. computer  101  shown in  FIG. 1 ) receives an unknown first session identifier from a client (e.g., client  153  shown in  FIG. 1 ) for a first communication session between the client and a server (e.g., server  151  shown in  FIG. 1 ), as described in block  404 . The MitM computer monitors Transport Layer Security (TLS) communication sessions between the client and the server. 
     As described in block  406 , in response to receiving the unknown first session identifier from the client for the first communication session between the client and a server, the MitM computer requests a second session identifier from the server for a second communication session between the server and the MitM computer. 
     As described in block  408 , the MitM computer generates a third session identifier for a third communication session between the MitM computer and the client. 
     As described in block  410 , the MitM computer establishes a fourth communication session between the server and the client using a combination of the second communication session and the third communication session. 
     As described in block  412 , the MitM computer detects an end of the fourth communication session. 
     As described in block  414 , subsequent to detecting the end of the fourth communication session, the MitM computer receives an invalid session identifier from the client for a fifth communication session between the client and the server. 
     As described in block  416 , in response to receiving the invalid session identifier from the client for the fifth communication session between the client and the server, the MitM computer transmits an instruction, to the client, to flush a session cache in the client, where flushing the session cache in the client forces the client and the server to establish a full TLS handshake in order to establish the fifth communication session between the client and the server. 
     The flowchart ends at terminator block  418 . 
     In an embodiment of the present invention, the MitM computer blocks the client from receiving the second session identifier. Thus, thus the client cannot establish a TLS session with the server using the TLS session identifier sent from the server to the MitM computer (i.e., the “inspector”). 
     In an embodiment of the present invention, the first, second, third, fourth, and fifth communication sessions described herein are via Transport Layer Security (TLS) connections. 
     In an embodiment of the present invention, the MitM computer inspects the fifth communication session in order to retrieve a decryption key for the fifth communication session that was created during the full handshake connection. The MitM computer then decrypts, using the decryption key that was retrieved from the fifth communication session, network traffic between the client and the server that flows during the fifth communication session. 
     In an embodiment of the present invention, the MitM computer transmits, to the server, a random session identifier to be used by the server as the second session identifier, such that the MitM computer generates the second session identifier. 
     In an embodiment of the present invention, the MitM computer transmits no session identifier to the server, such that the server generates the second session identifier. 
     In various embodiments of the present invention, the server is a webpage server and the client is a computer that is executing a web browser; the server is an email server and the client is a computer that is executing an email application; the server is a Voice over Internet Protocol (VoIP) server and the client is a VoIP client device; etc. 
     The present invention may be implemented in one or more embodiments using cloud computing. Nonetheless, it is understood in advance that although this disclosure includes a detailed description on cloud computing, implementation of the teachings recited herein are not limited to a cloud computing environment. Rather, embodiments of the present invention are capable of being implemented in conjunction with any other type of computing environment now known or later developed. 
     Cloud computing is a model of service delivery for enabling convenient, on-demand network access to a shared pool of configurable computing resources (e.g. networks, network bandwidth, servers, processing, memory, storage, applications, virtual machines, and services) that can be rapidly provisioned and released with minimal management effort or interaction with a provider of the service. This cloud model may include at least five characteristics, at least three service models, and at least four deployment models. 
     Characteristics are as follows: 
     On-demand self-service: a cloud consumer can unilaterally provision computing capabilities, such as server time and network storage, as needed automatically without requiring human interaction with the service&#39;s provider. 
     Broad network access: capabilities are available over a network and accessed through standard mechanisms that promote use by heterogeneous thin or thick client platforms (e.g., mobile phones, laptops, and PDAs). 
     Resource pooling: the provider&#39;s computing resources are pooled to serve multiple consumers using a multi-tenant model, with different physical and virtual resources dynamically assigned and reassigned according to demand. There is a sense of location independence in that the consumer generally has no control or knowledge over the exact location of the provided resources but may be able to specify location at a higher level of abstraction (e.g., country, state, or datacenter). 
     Rapid elasticity: capabilities can be rapidly and elastically provisioned, in some cases automatically, to quickly scale out and rapidly released to quickly scale in. To the consumer, the capabilities available for provisioning often appear to be unlimited and can be purchased in any quantity at any time. 
     Measured service: cloud systems automatically control and optimize resource use by leveraging a metering capability at some level of abstraction appropriate to the type of service (e.g., storage, processing, bandwidth, and active user accounts). Resource usage can be monitored, controlled, and reported providing transparency for both the provider and consumer of the utilized service. 
     Software as a Service (SaaS): the capability provided to the consumer is to use the provider&#39;s applications running on a cloud infrastructure. The applications are accessible from various client devices through a thin client interface such as a web browser (e.g., web-based e-mail). The consumer does not manage or control the underlying cloud infrastructure including network, servers, operating systems, storage, or even individual application capabilities, with the possible exception of limited user-specific application configuration settings. 
     Platform as a Service (PaaS): the capability provided to the consumer is to deploy onto the cloud infrastructure consumer-created or acquired applications created using programming languages and tools supported by the provider. The consumer does not manage or control the underlying cloud infrastructure including networks, servers, operating systems, or storage, but has control over the deployed applications and possibly application hosting environment configurations. 
     Infrastructure as a Service (IaaS): the capability provided to the consumer is to provision processing, storage, networks, and other fundamental computing resources where the consumer is able to deploy and run arbitrary software, which can include operating systems and applications. The consumer does not manage or control the underlying cloud infrastructure but has control over operating systems, storage, deployed applications, and possibly limited control of select networking components (e.g., host firewalls). 
     Deployment Models are as follows: 
     Private cloud: the cloud infrastructure is operated solely for an organization. It may be managed by the organization or a third party and may exist on-premises or off-premises. 
     Community cloud: the cloud infrastructure is shared by several organizations and supports a specific community that has shared concerns (e.g., mission, security requirements, policy, and compliance considerations). It may be managed by the organizations or a third party and may exist on-premises or off-premises. 
     Public cloud: the cloud infrastructure is made available to the general public or a large industry group and is owned by an organization selling cloud services. 
     Hybrid cloud: the cloud infrastructure is a composition of two or more clouds (private, community, or public) that remain unique entities but are bound together by standardized or proprietary technology that enables data and application portability (e.g., cloud bursting for load-balancing between clouds). 
     A cloud computing environment is service oriented with a focus on statelessness, low coupling, modularity, and semantic interoperability. At the heart of cloud computing is an infrastructure comprising a network of interconnected nodes. 
     Referring now to  FIG. 5 , illustrative cloud computing environment  50  is depicted. As shown, cloud computing environment  50  comprises one or more cloud computing nodes  10  with which local computing devices used by cloud consumers, such as, for example, personal digital assistant (PDA) or cellular telephone  54 A, desktop computer  54 B, laptop computer  54 C, and/or automobile computer system  54 N may communicate. Nodes  10  may communicate with one another. They may be grouped (not shown) physically or virtually, in one or more networks, such as Private, Community, Public, or Hybrid clouds as described hereinabove, or a combination thereof. This allows cloud computing environment  50  to offer infrastructure, platforms and/or software as services for which a cloud consumer does not need to maintain resources on a local computing device. It is understood that the types of computing devices  54 A- 54 N shown in  FIG. 5  are intended to be illustrative only and that computing nodes  10  and cloud computing environment  50  can communicate with any type of computerized device over any type of network and/or network addressable connection (e.g., using a web browser). 
     Referring now to  FIG. 6 , a set of functional abstraction layers provided by cloud computing environment  50  ( FIG. 5 ) is shown. It should be understood in advance that the components, layers, and functions shown in  FIG. 6  are intended to be illustrative only and embodiments of the invention are not limited thereto. As depicted, the following layers and corresponding functions are provided: 
     Hardware and software layer  60  includes hardware and software components. Examples of hardware components include: mainframes  61 ; RISC (Reduced Instruction Set Computer) architecture based servers  62 ; servers  63 ; blade servers  64 ; storage devices  65 ; and networks and networking components  66 . In some embodiments, software components include network application server software  67  and database software  68 . 
     Virtualization layer  70  provides an abstraction layer from which the following examples of virtual entities may be provided: virtual servers  71 ; virtual storage  72 ; virtual networks  73 , including virtual private networks; virtual applications and operating systems  74 ; and virtual clients  75 . 
     In one example, management layer  80  may provide the functions described below. Resource provisioning  81  provides dynamic procurement of computing resources and other resources that are utilized to perform tasks within the cloud computing environment. Metering and Pricing  82  provide cost tracking as resources are utilized within the cloud computing environment, and billing or invoicing for consumption of these resources. In one example, these resources may comprise application software licenses. Security provides identity verification for cloud consumers and tasks, as well as protection for data and other resources. User portal  83  provides access to the cloud computing environment for consumers and system administrators. Service level management  84  provides cloud computing resource allocation and management such that required service levels are met. Service Level Agreement (SLA) planning and fulfillment  85  provide pre-arrangement for, and procurement of, cloud computing resources for which a future requirement is anticipated in accordance with an SLA. 
     Workloads layer  90  provides examples of functionality for which the cloud computing environment may be utilized. Examples of workloads and functions which may be provided from this layer include: mapping and navigation  91 ; software development and lifecycle management  92 ; virtual classroom education delivery  93 ; data analytics processing  94 ; transaction processing  95 ; and TLS session processing  96 , which performs one or more of the features of the present invention described herein. 
     The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. 
     The corresponding structures, materials, acts, and equivalents of all means or step plus function elements in the claims below are intended to include any structure, material, or act for performing the function in combination with other claimed elements as specifically claimed. The description of various embodiments of the present invention has been presented for purposes of illustration and description, but is not intended to be exhaustive or limited to the present invention in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the present invention. The embodiment was chosen and described in order to best explain the principles of the present invention and the practical application, and to enable others of ordinary skill in the art to understand the present invention for various embodiments with various modifications as are suited to the particular use contemplated. 
     Any methods described in the present disclosure may be implemented through the use of a VHDL (VHSIC Hardware Description Language) program and a VHDL chip. VHDL is an exemplary design-entry language for Field Programmable Gate Arrays (FPGAs), Application Specific Integrated Circuits (ASICs), and other similar electronic devices. Thus, any software-implemented method described herein may be emulated by a hardware-based VHDL program, which is then applied to a VHDL chip, such as a FPGA. 
     Having thus described embodiments of the present invention of the present application in detail and by reference to illustrative embodiments thereof, it will be apparent that modifications and variations are possible without departing from the scope of the present invention defined in the appended claims.