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Mention simple example:
It is extremely easy for a Network Operator of a particular AS to find out if and how another AS can be reached. All he has to do, is to look at the current routing table for the path from his AS to the target AS. This would be sufficient for one-way communication, but in practice, most communication is two-way and there is no-way for the network operator to tell if the target AS has route back to source-AS. Historical information is also essential when trying to debug problems that only show up now and again. Specifically, the routing table doesn’t indicate when a route was last announced or withdrawn.
Default-free routing table contains routes to all globally known networks. This means that a default-free router, i.e. Internet Backbone Router, actively decides where to send packets with a destination outside the AS to which the router belongs, and not forward it, by default, to another router.
By default, EBGP TTL=1, peers are directly connected. By default, Multi-hop EBGP, TTL=255, peer NOT directly connected. Curiosa: IBGP TTL=255, because IBGP peers are usually NOT directly connected. Sun Enterprise 420 database server called Abcoude.
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Running dbinsert on RRC00 (sql over network) not a problem – plenty of bandwidth
MRT software includes multi-protocol IPv4/IPv6 routing daemons and routing analysis/simulation tools. Hecate – RRC00, Iris – RRC01, Pag – RRC02, Cres – RRC03, Vis – RRC04, Dugi – RRC05, Susak – RRC06
ASInuse – Last time certain AS was seen on the Internet
Search by AS – All prefixes seen originating from specified AS.
Search by prefix – Prefix and associated AS paths seen by RIS (originating AS’s) Looking Glasses  – At seven locations: RIPE NCC, LINX, SFINX, AMS-IX, CIXP, VIX, NSPIXP2 Show IP BGP displays the BGP table. In our case, the BGP table entry for a particular network because of hardware performance restrictions.
Show IP BGP summary displays a summary of the entire BGP table.
Raw data - Data only stored in MySQL for 3 months, Raw Data since the beginning of the project. Ris-report plots statistics based on RIS data (currently up to 24 hours lag, working on 1-2 hours lag)
AS702 – UUnet Europe
Click on link – 158.116.242.0/23 interested me
Both 158.116.0.0/16 and 158.116.242.0/23 seen by ris (Probably IGP and DDR or something as backup between Corp HQ and office in Europe)
Best route -> loc pref same, consider shortest AS path (3 as hops), best MED (10) Best route 2 -> loc pref and aspath same (2 AS-hops) , no med, trust oldest route AS2914 – Verio INC, owned by Japanese NTT Communications  (Verio has own class B: 129.250.0.0/16)
Netname: SOLECTRON
   Netblock: 158.116.0.0 - 158.116.255.255
Old class B address space (AS18882) – PI space 158.116.242.0/23 assigned to remote office in Ireland, announced by AS702 (Alder.net) – UK & Ireland, AS701(UUnet) – US, 18882 single-homed AS peering with AS701.
How RRC00 sees the announcement of Solectron’s IP address space
MRTG – Multi RouterTraffic Grapher (Plots routing information)
The Multi Router Traffic Grapher (MRTG) is a tool to monitor the traffic load on network-links. MRTG generates HTML pages containing GIF images which provide a LIVE visual representation of this traffic.
GNUplot: Histograms, Pie-charts that RRD cannot do.
Five RRD dBases per RRC. Implemented on RRC00 and RRC01. Explain a bit about Thomas Franchetti’s SQL2RRD and new implementation of it .RRD is dbase. What is .s2r? They contain the SQL statement used for data inserted into RRD. Perl scripts use RRDTool to plot graphs. New implementation: New program developed by Softies that will insert data into RRD directly from binary format. Improves performance because querying dBase is eliminated. Idea is using this process for time-sensitive data, eg count, withdrawals etc. SQL2RRD will probably still be implemented for experimental purposes or less time-sensitive stuff, e.g. AS path length statistics, AS’s or Prefixes seen, ratios allocated/ annouced etc, that might be easier to derive for SQL before inserting into RRD. Dead parts in graphs – 1. Their box, Our box, dbinsert (data missing in MySQL 4. Sql2rrd problems (RRD cannot go back in time to fix ‘no data spots’).
Usually some instabilities due to reboots, policy changes, physical / data-link layer problems etc (also pathological updates). Most networks are reachable but high levels of update activity can kill router’s CPU and Mem BGP message storms – high activity kills keep-alives which kills the BGP sessions – withdrawals propagate through-out the Internet – end-user experiences slow or no performance – solution: higher IP precedence for BGP keepalives – router still services keepalives even though congested