A Quick Networking Terminology Primer (For Dave) - Page 1
Forum section: electronics / projects

author: German_EE
author_rank: Super Contributor
timestamp: March 08, 2016, 11:30:43 am
content: After the problems Dave was having with his Pitya board I decided to pass on the following. This information is OS neutral and applies to Linux, MS Windows, Mac OSX, BSD and everything else.DEFAULT GATEWAYThe entry that tells your computer or device where to find everything. Unless told otherwise use the I.P. Address of your router.DHCPDynamic Host Configuration Protocol. It's a way for your computer or device to download all of the network settings automatically BUT for it to work you must put the address of your router in the Default Gateway setting so it knows where to get the settings from.DNSThe Domain Names System converts an IP address into something understood by humans such aswww.eevblog.com. Normally the DNS entries are configured by DHCP but if they're not then put in the I.P. Address of your router.MAC ADDRESSThe address set in hardware of your device. In theory every MAC Address in the world is unique as they are assigned by the manufacturer of the product. There should be no need to change this setting.IP4 / IP6IPv4 is the old way of doing things with addresses such as 192.168.0.1 but these numbers have now run out. The new standard is IPv6 which is best avoided on a small internal network unless you specifically want to learn about this technology. If you appear to be having network problems then try disabling IP6 on devices one by one and the problems could go away.

author: samnmax
author_rank: Regular Contributor
timestamp: March 08, 2016, 02:13:25 pm
content: Quote from: German_EE on March 08, 2016, 11:30:43 amUsually, for a network interface configured with DHCP, the Default Gateway setting is also obtained automatically from the network. When you plug in an ethernet card set for DHCP, a DHCPDISCOVER message is broadcasted to all machines on your LAN segment, so your router then replies with the automatic configuration for that machine, including IP address, DNS server, and default gateway. At least that's what SHOULD happen

author: botcrusher
author_rank: Regular Contributor
timestamp: March 09, 2016, 01:51:48 pm
content: Little quick note on ipv4 adresses:192.168.x.x numbers are reserved for private networks, ex: at home or a medium sized office.10.x.x.x numbers give a massive range, and are designated for massive interal networks.Ex: a school district intranet127.0.0.1 is localhost, meaning if you run a server on a machine, in order to reach it from that machine, you use this number. A great example of this is a Linux X11 display(Note: most all things allow you to actually type 'localhost' for the same result)0.0.0.0 quite simply means ALL THE THINGS. If It's a server with multiple internet connections, or a laptop with wifi+Ethernet it will listen for a connection on all interfaces.

author: German_EE
author_rank: Super Contributor
timestamp: March 09, 2016, 09:31:16 pm
content: My home network uses the 192.168.0.x address range but when the cable modem logs on first thing in the morning the WAN address is in the 10.x.x.x range. So, it looks like the network path is:Home network------->Cable Modem--------->Cable Co Internal Network------------>Cable Co Router----------->INTERNET192.168.0.x NAT 10.x.x.x NAT

author: 1xrtt
author_rank: Regular Contributor
timestamp: March 09, 2016, 09:55:33 pm
content: Quote from: botcrusher on March 09, 2016, 01:51:48 pmhttps://tools.ietf.org/html/rfc1918

author: Kohanbash
author_rank: Regular Contributor
timestamp: March 11, 2016, 01:23:38 am
content: I generally use 8.8.8.8 as a DNS server since it is easy to remember and belongs to Google and works well.Also since it is easy to remember I often use it for ping tests to verify network connections while taking DNS out of the picture.http://robotsforroboticists.com/networking-robots-crash-course/

author: Skimask
author_rank: Super Contributor
timestamp: March 11, 2016, 03:43:24 am
content: ALL of the above information obtainable from literally millions of sites, least of which might be wikipedia.

author: German_EE
author_rank: Super Contributor
timestamp: March 11, 2016, 08:47:14 am
content: True, but Dave was having problems so I decided to help out.

author: jc101
author_rank: Frequent Contributor
timestamp: March 11, 2016, 09:21:27 am
content: If you have an IP assigned of 169.254.x.x then your machine asked for an IP address via DHCP but didn't get one, so picked one randomly from this range.Makes a quick and easy check to see if DHCP is working OK, and that you have a network path through to the DHCP server itself.