And Internet Looking Glass allows you to view the BGP table in real time on the Internet.
Round views dot org or route views dot org has a list of routers that you can connect to to view Internet
routing tables in real time so I'm gonna use putty to connect using Telnet to round views talk about
views dot org.
I'll make the font bigger so that you can read it more easily.
So what I've done is connected to rot vs.
We need to use the user name all reviews to log in.
We don't get access to privilege mode or we enable mode on the router but we could use commands such
as Show IP BGP summary to view information about the BGP routing table.
Now we'll discuss some of these commands in the upcoming videos.
So don't worry too much about the exact syntax at the moment.
What you'll notice Firstly is it took a long time for the information to appear but there's the command
show IP BGP summary the router has a router I.D. in a similar way to OSP for EAI GOP.
The autonomous system that the strata belongs to is 6 4 4 7.
The BGP table version number is this Every time there's a change in the BGP routing table.
This entry increment by 1.
In other words when a new route is added or a route is removed the table number will change by 1 and
I'll show you in a moment the number of changes that have taken place while I've been speaking.
These are BGP neighbors.
In other words these are routers that this local router has a connection to and as you can see there's
a large number of BGP neighbors so scroll up to the top.
There's the first BGP neighbor we're using BGP version forward to communicate with us neighbor BGP version
4 is the current release of BGP that neighbor is in this autonomous system 3 3 5 6 the number of messages
sent and received are as follows.
And what you'll notice on the right hand side is that five hundred and ninety one thousand eight hundred
seventy three rights have been learnt from this neighbor from this neighbor.
Five hundred ninety four thousand or drafts have been lent.
And if we scroll down you'll notice a large number of rights.
Some of them going over 600000 have been learnt from various neighbors this kind of writing table and
number of relationships requires a lot of memory and processing power on the router and you can see
the number of bytes used of memory for path entries as well as network entries.
So a large amount of memory is being consumed on this writer to manage these relationships.
And to keep the BGP table running show IP round summary will allow us to see the number of runs in the
IP routing table.
Now you need to add networks and subnets together gives us a IP routing table on this router of about
650000 runs very large amount of runs in the routing table on this Radha once again a whisper for G.I.
Joe.
He would not be able to handle this size of routing table.
They would simply not be able to cope with the number of runs.
Let's have a look at the number of changes in the BGP routing table in this amount of time that I've
been speaking.
So show IP BGP summary.
So this is the BGP table version at the moment
and previously this was the BGP table version.
So how many changes have taken place while I've been speaking.
So this number minus or subtract this number gives us two thousand seven hundred thirteen changes in
a very short amount of time
and just to demonstrate that again I'll top shot clock show IP BGP summary.
So it's almost eleven thirty seven when I started typing this command show clock
eleven thirty seven.
So it's a less than a minute later.
So 30 720 so there's the new table number version and previously this was the table number
so in the period of less than a minute we had about a hundred writing changes.
Now you can imagine what that would do to a writing protocol such as so SPF the 0 SPF SPF algorithm
would continuously be recalculating the best route to a destination.
And this number of changes would simply overwhelm SPF.
So BGP is once again an exterior Gateway writing protocol.
It runs the internet and can handle a massive amount of runs being advertised by neighbours and being
held in the BGP writing table.
The biggest network that we know of today the Internet is run by BGP.
So unless there is another network that we don't know about on Saturn or another planet the biggest
network is run by BGP.