1) Using publically accessible Looking Glass and Route Servers please determine how the following networks are connected to the internet. Create a quick sketch of each.
Hints:
f) What are the names of the networks we are looking at? How is this determined?
g) How does this provide a better or worse view than using traceroute servers?
h) What might be some problems with this approach?
i) Would you get variable results depending on the network you are looking from? What about from a different location within the same network?
2) You are a local ISP (one city) in Little Rock Arkansas. Your customer base is growing quickly as the natives discover the In-ter-net.
b) Business is good...you decide to add a T-3 internet connection to UUNet and use the T-1 for backup. How would routing now be set up?
c) You sign a deal with a local DSL Provider that will double the size of your customer base. You decide to add a 2nd T-3 internet connection to AboveNet. How might your routing look now? What considerations would you make when adding a 2nd provider? Do you still need the T-1 for backup...why or why not?
d) Wow...your sales folks are good...they sold some capacity to Yahoo.com Unforunately your T-3 connection to UUNet is congested outbound as all those eyeballs in UUNet start browsing Yahoo. Assume that Yahoo is using four /24s of IP space which you are announcing to your providers. Your ISP users are split into four /20s which you are announcing to your providers. How might you move some of that outbound traffic to the uncongested AboveNet T-3.
e) You just bought a local ISP that was going out of business. You know have 4x as many users. Unforunately your T-3 to AboveNet is now congested inbound as all your users start to browse the internet. How might you move some of that inbound traffic to the uncongested UUNet T-3.
3) Do a web search on AS7007. Explain.
4) For each of the following 'sho ip bgp 66.0.0.0 255.0.0.0' outputs...which of the 3 possible routes is the best route and why? Show the BGP decision process for each.
a)
BGP routing table entry for 66.0.0.0/8, version 9361469
Paths: (1 available, best #1)
55
5.0.0.1 (metric 76) from 5.0.0.1 (5.0.0.1)
Origin IGP, metric 1000, localpref 100, valid, internal
Community 5:550
3549 55
5.0.0.5 (metric 94) from 5.0.0.5 (5.0.0.5)
Origin IGP, metric 900, localpref 80, valid, internal
Community: 5:999
701 55
5.0.0.9 (metric 98) from 5.0.0.9 (5.0.0.9)
Origin IGP, metric 800, localpref 80, valid, internal
Community: 5:570
b)
BGP routing table entry for 66.0.0.0/8, version 9361469
Paths: (1 available, best #1)
55
5.0.0.1 (metric 76) from 5.0.0.1 (5.0.0.1)
Origin IGP, metric 1000, localpref 100, invalid, internal
Community 5:550
3549 55
5.0.0.5 (metric 94) from 5.0.0.5 (5.0.0.5)
Origin IGP, metric 900, localpref 80, valid, internal
Community: 5:560
701 55
5.0.0.9 (metric 98) from 5.0.0.9 (5.0.0.9)
Origin IGP, metric 800, localpref 80, valid, internal
Community: 5:570
c)
BGP routing table entry for 66.0.0.0/8, version 9361469
Paths: (1 available, best #1)
1239 55
5.0.0.1 (metric 76) from 5.0.0.1 (5.0.0.1)
Origin IGP, metric 1000, localpref 80, valid, internal
Community 5:550
55
5.0.0.5 (metric 94) from 5.0.0.5 (5.0.0.5)
Origin IGP, metric 900, localpref 80, valid, internal
Community: 5:999
701 55
5.0.0.9 (metric 98) from 5.0.0.9 (5.0.0.9)
Origin IGP, metric 800, localpref 80, valid, internal
Community: 5:570
d)
BGP routing table entry for 66.0.0.0/8, version 9361469
Paths: (1 available, best #1)
55
5.0.0.1 (metric 76) from 5.0.0.1 (5.0.0.1)
Origin IGP, metric 1000, localpref 80, valid, internal
Community 5:550
55
5.0.0.5 (metric 94) from 5.0.0.5 (5.0.0.5)
Origin IGP, metric 1000, localpref 80, valid, internal
Community: 5:999
55
5.0.0.9 (metric 98) from 5.0.0.9 (5.0.0.9)
Origin IGP, metric 1000, localpref 80, valid, internal
Community: 5:570
e)
BGP routing table entry for 66.0.0.0/8, version 9361469
Paths: (1 available, best #1)
55
5.0.0.1 (metric 76) from 5.0.0.1 (5.0.0.1)
Origin IGP, metric 999, localpref 80, valid, internal
Community 5:1260
55
5.0.0.5 (metric 94) from 5.0.0.5 (5.0.0.5)
Origin EGP, metric 793, localpref 80, valid, internal
Community: 5:999
55
5.0.0.9 (metric 98) from 5.0.0.9 (5.0.0.9)
Origin UNK, metric 357, localpref 80, valid, internal
Community: 5:139 6:454 7:492