Minutes from RIPE 40

R I P E  4 0    P R A G U E
Routing Working Group Session
3-October-2001  Minutes

Chair:          Joao Luis Silva Damas (i p o Joachim Schmitz - JS395-RIPE)
Scribe:         Matthew Williams
Participants:   88


A. Preliminaries

   Joao introduced himself, welcomed us all to the meeting and then handed
   out the participants' list. Matthew Williams from the RIPE-NCC volunteered
   to take the minutes.

   The agenda for this session and minutes from the previous meeting at RIPE39
   were approved without further ado.

   Action points from earlier meetings:

   37.R1 on C.Panigl, P. Smith, D. Karrenberg, J. Schmitz
      Updates to RIPE-210
      -done-

      The final draft document (v2.0) has been sent to the Routing-WG
      mailing list.

   37.R2 on RIS team, Henk Uijterwaal
      Implement route flap analysis from RIS data
      -ongoing-

   39.R1 on J.Schmitz, D.Kessens
      Initiate IPv6 IRR task force
      -ongoing-

   39.R2 on D.Karrenberg
      Provide 'Golden Network' web page
      -done-

      The web page can be found at URL:
      http://www.golden-networks.net/


B. Henk Uijterwaal: Routing Information Service, Status and Plans

   Presentation available at URL:
   http://www.ripe.net/ripencc/pub-services/np/Talks/0110_RIPE40

   There have been some changes to the team. Three new staff members
   have joined and one has left. Next year in February, a student focusing
   on route flaps and/or black holes will also join the team. One of the new
   functions, the Customer Liaison Engineer, will be responsible for 
 encouraging
   more interaction between New Projects and users of its services. Two 
 mailing
   lists, ris-ix@ripe.net and ris-users@ripe.net, have been created for this
   purpose. Ris-ix will be used specifically for correspondence between 
 RIPE-NCC
   and hosts of Route Collectors, while ris-users will be open to anyone 
 who uses
   RIS or RIS' raw data.

   Some links to research based on the RIS' data have been added to the 
 web site:
   - Thomas Franchetti's Thesis, 'Internet Routing Analysis Provided by
     the RIS Report', provides the most current technical description of the
     RIS and RIS Report. It also includes some interesting practical examples
     on RIS usage.
     (URL: http://www.ripe.net/ris/analysis.html)

   - Various plots and tables from RIPE-NCC and MAE-East data by Olaf
     Mannel at the University of Saarbrucken.
     (URL: http://www.net.uni-sb.de/~olafm)

   - Dartmouth College/Renesys Inc's 'Global Routing Instabilities during
     Code Red II and Nimda Worm Propagation'
     (URL: http://www.renesys.com/projects/bgp_instability)

   Currently, route collectors are present at:
   - RIPE-NCC
   - LINX, London
   - SFINX, Paris
   - AMS-IX, Amsterdam
   - CIXP, Geneva
   - VIX, Vienna
   - NSPIXP2, Otemachi (Tokyo)

   Total of 162 BGP sessions

   The route collector in Tokyo, which has been deployed in collaboration with
   APNIC, will provide the RIS with a view from a completely different angle.
   There are further plans to install one or two more route collectors in 
 the US
   for the same reason as mentioned above. The additional value of adding 
 more
   boxes can be judged by studying the differences in BGP routing information
   between different collectors.

   There have been some improvements to the RIS  since the last meeting. 
 It is now
   possible to make queries either by AS or Prefix, which should be 
 clearer for the
   user. The Zebra logs can now be downloaded from the web site and NTP 
 problems
   with raw data are fixed. Two other services, ASInuse and the RIS report 
 have
   been brought online. Immediate plans include improving the response 
 time of queries
   and providing more FAQs and general documentation. In 2002, the RIS 
 team plan to
   deploy additional route collectors, develop user training and implement
   a graphical presentation of AS maps. The main research projects comprise
   of studying route flapping, investing dark address space and 
 reconstructing
   the Internet routing table from RIS' raw data.


C. Philip Smith: BGP Flaps

   Slides available at URL:
   http://www.ripe.net/ripe/meetings/archive/ripe-40/presentations/
          routing-bgpflaps/

   Philip Smith presented some interesting observations regarding BGP flaps
   based on Geoff Huston's data at URL: http://www.telstra.net/ops/bgp/
   bgp-upd-entries.html. The main focus of this study was the behavior of
   different prefix sizes in today's Internet with regard to the dampening
   values chosen in 1997 (RIPE-210).

   Main observations when analyzing BGP updates of the last 14 days:
   - Forwarding Information Base (FIB): 110k prefixes
   - Average updates per hour: 713
   - Average prefix size of updates: 23.05

   BGP Updates per hour, sorted:
   /24 - 449 updates
   /23 - 51 updates
   /22 - 45 updates
   /19 - 41 updates
   /20 - 39 updates
   /16 - 35 updates
   /21 - 29 updates

   This means that 60% of all updates were caused by /24s. However, the route
   dampening values after three flaps have remained unchanged in the update
   to RIPE-210:
   - /24s and longer prefixes, suppressed for 60 minutes
   - /22s and /23s, suppressed for 45 minutes
   - The rest are suppressed for 30 minutes

   Mr Smith's preliminary conclusions were that /24s maybe should be 
 dampened more
   aggressively and that values for /22s and /23s should be extended to 
 include /16s
   and then the entire range from /19s to /23s. Dampening values for the rest
   seem to be working satisfactory. Geoff Huston has only been collecting
   data for the last couple of months,i.e. more research needs to be done. 
 There
   will be another presentation at the next RIPE meeting.

   Q: Why are /24s flapping so much?
   Q: Where are the /8 flaps coming from?
   A: Currently, questions like where and who cannot be answered. More 
 research
      needs to be done before the next meeting.


D. Philip Smith: Multi-homing Document

   Presentation available at URL:
   http://www.ripe.net/ripe/meetings/archive/ripe-40/presentations/
          routing-multihoming/

   Kurt Keyser, Abha Ahuja, Joachim Schmitz and Philip Smith intend
   on authoring a document for LIRs on multihoming with some
   advise regarding common situations. Progress is slow at the moment.
   An update will be presented at the next RIPE meeting.

   Q: Is there a draft available for scrutiny?
   A: Not yet, but feedback from the WG is very welcome.


E. Florent Parent: IPv6 Routing Policies using RPSL

   Presentation available at URL:
   http://www.ripe.net/ripe/meetings/archive/ripe-40/presentations/
          ipv6-routing-rpsl-ripe40.pdf

   Florent Parent gave us an update on RPSL and IPv6. At this time,
   the specification for RPSL (RFC2622) does not cover
   IPv6 usage for routing policies. However, there is support for
   the new version of IP in RPSL. Immediate tasks will be
   documenting IPv6 usage in current classes and defining new attributes
   where required.

   The current classes used in the 6Bone whois database are ipv6-site
   and inet6num. They are both defined in an IETF draft, which can be
   downloaded from: http://whois.6bone.net/~david/6bone/draft-ietf-ngtrans-
   6bone-registry-xx.txt. Mr Parent went on to discuss the
   implications of IPv6 routing policies when using current RPSL classes.
   There is much work to be done. The next steps will be to form a task force
   focusing on IPv6 RPSL, sending the current IETF draft to the mailing list
   for scrutiny and adding support in RAtoolset for the new IP version.
   Those interested in participating in the task force should contact
   Mr Parent (email:Florent.Parent@viagenie.qc.ca).

   Q: What is the name of the mailing list?
   A: The chair mentioned that it is hosted by RIPE-NCC as
      rpslng@ripe.net (majordomo).


F. Roger Gottsponer: How to secure your job: Implement MPLS VPNs

   Presentation available at URL:
   http://www.ripe.net/ripe/meetings/archive/ripe-40/presentations/
          mpls-routing-ripe40/

   Mr Gottsponer from Nextra in Switzerland shared with us lessons they
   had learnt when implementing and running a real life MPLS/VPN network.
   This presentation was instigated by the MPLS tutorial at RIPE39 and
   the fact that Nextra has been running a national MPLS-VPN network for 2.5
   years. The international network has been in place since one year back.

   Their experiences are that MPLS provides one with lots of interesting
   features, such as new customer services (VPNs) and money-saving 
 opportunities
   through traffic engineering, but it does also make operations more
   problematic. Another downside is the fact that some features may not be
   'VPN-aware', i. e. NAT, firewalls. However, most problems are not 
 related to
   technology.

   Mr Gottsponer went on to talk about general concepts and the actual
   deployment of MPLS/VPNs. He did mention some interesting observations
   regarding using traceroute on a MPLS network and considerations when
   securing your Provider Edge (PE) routers.

   The problem with traceroute is that it will send an ICMP packet with a
   TTL of 0 to the second router in the Label Switch Path (LSP) between the
   two PE routers. Because the second router only looks at the layer 2
   header, the packet will be sent all the way to the PE router at the other
   end of the LSP before the ICMP TIME_EXCEEDED response is sent back to the
   transmitting station. One will therefore see observe strange latencies 
 when
   using a non-mpls-aware traceroute utility.

   The second issue dealt with securing PE routers against unsolicited telnet
   requests. Mr Gottsponer's main recommendations were:
   - Only use host routes for network management stations
   - Point host routes to null interfaces in each of the customers'
     Virtual Routing Forwarding Tables (VRFs)
   - Filter routing updates from customers. Do not accept all internal
     address ranges.
   - Use loopback addresses and IP extended access-lists on PE routers

   There were no questions after the presentation.


Y. Input from other WGs

   IPv6 WG:
   As mentioned previously, interested parties are welcome to join the 
 IPv6 RPSL
   task force by sending an email to: Florent.Parent@viagenie.qc.ca


Z. AOB

   none


Summary of Open Action Points from the Routing WG

   37.R2 on RIS team, Henk Uijterwaal
      Implement route flap analysis from RIS data
      -ongoing-

   39.R1 on J.Schmitz, D.Kessens, F.Parent
      Initiate IPv6 IRR task force
      -ongoing-

   40.R1 on Kurt Keyser, Abha Ahuja, Joachim Schmitz and Philip Smith
      Creating a 'Multihoming Document' for LIRs
      -new-


Joao Luis Silva Damas, Joachim Schmitz, Matthew Williams, October 2001