Friday, October 30, 2015

Part II Principles of Communications, 2015, to Oct 30

Previously, Compact routing, Central routing (fibbing to link state),&path vector

This week covered
interdomain routing, including AS paths and deadlocks,
for which see interdomain revision notes/slides
+
multicast,
+
random routing

Just started on error and flow control.
[As usual, wikipedia is great on gaussian elimination ]

Pretty much as per schedule

Friday, October 23, 2015

Part II Principles of Communications, 2015, to Oct 23

This week has been about inter-domain routing, and BGP.
Covered background business relationships (peering, customer/provider etc), the protocol, the attributes/selection, SPP, and discussed scaling, convergence, and problems (like bad gadgets, wedgies) - as always, data is out of date, but Geoff Huston to the rescue...

Thursday, October 15, 2015

Part II Principles of Communications, 2015

This week (to Dec 16) I should have covered the graph material (random graphs + alpha&beta models of small world/clustered graphs), and
Compact and Centralised routing - viz
http://www.cl.cam.ac.uk/teaching/1516/PrincComm/slides/schedule-2015.html

On graphs and networks there's a new really nice book by Jon Kleinberg


There's some lack of precision about the terms "small world" but basically, (wikipedia is your friend) a scale-free network refers to the power law degree distribution, and consequential small diameter (and some clustering), which leads to the small world property. Not all small world networks are scale free, but scale free networks are small world...