# Presentation: 102291

## LambdaStation

- Phil DeMar
-  Don Petravick
- BNL
- Oct. 25, 2004

## Overview

- The Problem Space
- Functional Description of LambdaStation
- Components of LambdaStation
- Technical Approach
- Case Study
- Test Environment
- Project Outline
- Current Status
- Summary

- Demar,  Petravick:  Lambda Station

- 10.07/2004

## The Problem

- Very high (1-10 Gb/s) bandwidth research networks becoming available
- Typically not intended for general network traffic
- Alternate paths for high impact data movement
- Vision of the future: optical networks & lots of λ’s
- Not integrated with facility production LANs
- Production systems & storage facilities not directly accessible
- Customized local access usually required...
- WAN paths difficult to effectively use
- Used mostly with prototypes or in demonstrations

- Demar,  Petravick:  Lambda Station

- 10.07/2004

## Proposed implementations don’t scale
Multi-homed end system model breaks down with multiple alternate paths
Graceful failover capability missing or very complex  
Virtual interface model difficult to administer & adds complexity on host systems 
Applications may need customization for each new technology or high-performance path
A last mile problem between advanced WAN & facility production LANs...

- Multi-homed end system model breaks down with multiple alternate paths
- Graceful failover capability missing or very complex
- Virtual interface model difficult to administer & adds complexity on host systems
- Applications may need customization for each new technology or high-performance path
- A last mile problem between advanced WAN & facility production LANs...

**The Problem (II)**

- Demar,  Petravick:  Lambda Station

- 10.07/2004

## Proposed Solution: LambdaStation

- LambdaStation: an alternate path selection service
- Agent to coordinate use of alternate WAN paths:
- _Dynamic_ configuration adjuster of local network devices
- Goal is _per-flow_ granularity for alternate path selection
- LambdaStation is a research project
- A 2-3 yr US Dept of Energy, Office of Science
- Fermilab and Caltech
- In very early stages of development
- Still in design phase
- Production network use is a ways off

- Demar,  Petravick:  Lambda Station

- 10.07/2004

## How LambdaStation Would Help

- Advanced research networks
- Offer alternate, high bandwidth WAN paths
- May be a scheduled resource
- Typically demands customized local access
- LambdaStation intended to:
- Facilitates application request for high bandwidth WAN path
- Coordinates alternate WAN path establishment
- Dynamically reconfigures LAN forwarding of application’s data

- Demar,  Petravick:  Lambda Station

- 10.07/2004

## Components of LambdaStation

- A network path controller with modules interfacing to:
- Advanced WANs
- Local network infrastructure
- Peer LambdaStations
- Local applications & middleware
- AA infrastructure
- Software on host systems to coordinate with LambdaStation

- Demar,  Petravick:  Lambda Station

- 10.07/2004

## Host Interactions

- Path request primitives:
- Flow identification:
- Source/dest address/port
- DSCP code point
- Possibly IP version
- Transfer characteristics
- Bytes, peak rate, duration
- Schedule (range)
- Path status primitives:
- Allocated bandwidth
- Path setup status
- Path termination status
- Normal or early abort...

- Demar,  Petravick:  Lambda Station

- 10.07/2004

## LAN Interactions

- LAN device forwarding reconfigurations
- Graceful alternate path setup & teardown
- ACL modifications at site egress point
- Customizable interface to fit site specifics
- Non-objectives:
- QoS
- Traffic policing

- Demar,  Petravick:  Lambda Station

- 10.07/2004

## WAN Interactions

- Capability for multiple alternate WANs
- Customizable interface to fit each WAN
- Provide abstract view for applications
- Path reservation
- Resource availability
- Scheduling
- Path setup/teardown
- Graceful...
- Non-objectives:
- QoS
- Link efficiency

- Demar,  Petravick:  Lambda Station

- 10.07/2004

## Remote Site Interactions

- Establish path symmetry
- Exchange traffic selectors
- Coordinate WAN path setup/teardown
- Ack LAN path reconfiguration
- Verify path continuity
- Implies concurrent connectivity via reserved & commodity network paths
- Inform of:
- Path termination
- Traffic termination

- Demar,  Petravick:  Lambda Station

- 10.07/2004

## Authorization & Authentication 

- Initial AA capability:
- LambdaStation internal
- Site-controlled
- But some trust-level between sites
- Longer term goal:
- Utilize VO AA infrastructure
- Raises site-level control issues

- Demar,  Petravick:  Lambda Station

- 10.07/2004

## Technical Approach

- Flow identification:
- Source/destination IP and DSCP code point tag
- Source/destination IP & Source/destination port #
- Local path forwarding reconfigurations:
- Based on policy routing ACLs
- Advanced WAN interface model:
- Site egress/ingress router to alternate path(s)
- Layer 2 site-to-site connections (vlan) or MPLS paths
- Transparent failover back to production path:
- Bandwidth limits or QBSS on fall-back traffic

- Demar,  Petravick:  Lambda Station

- 10.07/2004

## Use Case

- FNAL SRM gets request to copy 3.5TB data set to CMS tier-2 site
- -  Transfer involves 3500 1GB files stored on 50 dCache systems
- SRM initiates data transfer optimized for production network path
- SRM makes alternate path request to local LambdaStation
- LambdaStation:
- -	Checks authentication & authorization
- -	Schedules & coordinates establishment WAN path
- -	Coordinates with remote site LambdaStation for symmetrical path
- -	Verifies alternate WAN path continuity
- -	Reconfigures local LAN for selective flow forwarding
- -	Notifies SRM that alternate path is established
- SRM makes parallelism changes to re-optimize data transfer
- SS Potentially shapes traffic to avoid congestion at pipe entrance.
- Path reservation expires; LambdaStation gracefully tears path down
- -	Remaining data movement traffic reverts to production network path
- -	LambdaStation notifies SRM of alternate path teardown
- SRM re-optimizes data transfer parallelism to complete the transfer

- Demar,  Petravick:  Lambda Station

- 10.07/2004

## Test Environment

- LambdaStation Project Sites:
- FNAL (US-CMS Tier-1 Center)
- Cal Tech (US-CMS Tier-2 Site)
- Working to include UCSD as well (US-CMS Tier-2 Site)
- CERN CMS Edge Computing also planned
- LambdaStation Test WANs:
- US DOE UltraScience Net
- Two 10 GE (OC192) lambda’s
- MPLS tunnels over DOE’s ESnet
- Sub-10GE chunk out of ESnet production network

- Demar,  Petravick:  Lambda Station

- 10.07/2004

## Project Outline

| Year 1 | LAN integration: | Dynamic LAN reconfiguration |
| --- | --- | --- |
|  | WAN integration: | Interface to DOE UltraScience Net;
Establish alternate path to Cal Tech |
|  | Application integration: | SRM allocated bandwidth awareness  |
| ---------------------- | ---------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------- |
| Year 2 | LAN integration: | Automated LAN path setup/teardown, & scheduling; Peer LambdaStation coordination |
|  | WAN integration: | Automated UltraScience Net WAN path setup/teardown & scheduling |
|  | Application integration: | VO sensitivity; Adapt storage systems to schedule transfers to path avail. |
| ---------------------- | ---------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------- |
| Year 3 | LAN integration: | Harden to production use quality |
|  | WAN integration: | Full integration w/ UltraScience Net; |
|  | Application integration: | Harden to production use quality |

- Demar,  Petravick:  Lambda Station

- 10.07/2004

## Current Status

- A “Pre-LambdaStation” prototype exists:
- Dynamically reconfigures LAN devices to forward select traffic over alternate paths
- End system-applied DSCP tags for special-treatment flows
- Prototype work-arounds:
- Manual input of reservation parameters
- Static alternate WAN path – no setup required
- Asymmetric – no reverse path setup
- Results:
- Alternate traffic path established & torn down cleanly
- Path reroute & failback unnoticed by application

- Demar,  Petravick:  Lambda Station

- 10.07/2004

## Summary

- LambdaStation’s role in data-intensive science:
- Dynamically connect production end-systems  to advanced high-performance wide-area networks
- Bring production-use systems to advanced networks
- Bring advanced networks to production-use applications
- LambdaStation’s status:
- Prototyping has demonstrated feasibility of dynamically reconfiguring local network paths for specific data flows
- Much work remains to be done for complete proof-of-concept
- It’s a research project...

- Demar,  Petravick:  Lambda Station

- 10.07/2004