Subject: Loss rate in US/E-Bone link

From: "Mr J.C. Evans" <[email-masked]>
Date: Fri, 8 Nov 1996 15:28:45 +0000 (GMT)

Hello,

Can anyone explain the very high loss rates in the US/E-Bone link and
to surfnet (i.e. is it something other than maxed-out link ?)

Are then any plans to improve the situation ?

Here's a mtrace done at 15:15 GMT, Friday 8th November on the
CBC Newsworld feed to here (The University of Liverpool, UK).

Best wishes,

Jonathan

Waiting to accumulate statistics... Results after 138 seconds:
 
  Source        Response Dest    Packet Statistics For     Only For Traffic
   * * *        138.253.32.15    All Multicast Traffic     From 131.136.234.103
     |       __/  rtt  376 ms    Lost/Sent = Pct  Rate       To 224.2.204.125
     v      /     hop -241 s     ---------------------     --------------------
128.167.252.196 collegepk-mbone1.bbnplanet.net 
     |     ^      ttl   32     1221/1602 = 76% 160 pps     2/261  =  1%  26 pps
     v     |      hop   54 ms 15955/21066= 76% 152 pps    19/3485 =  1%  25 pps
137.39.43.34    MBONE1.UU.NET  
     |     ^      ttl   64       31/1018 =  3% 101 pps     5/259  =  2%  25 pps
     v     |      hop  -96 s    329/13480=  2%  97 pps    19/3466 =  1%  25 pps
192.41.177.247  mae-bone.psi.net 
     |     ^      ttl   65       13/1203 =  1% 120 pps     2/254  =  1%  25 pps
     v     |      hop  108 s    254/16325=  2% 118 pps    55/3447 =  2%  24 pps
198.67.134.250  schnell.ebone.net 
     |     ^      ttl   66      149/2337 =  6% 233 pps    15/252  =  6%  25 pps
     v     |      hop   98 s   2013/30916=  7% 224 pps   204/3392 =  6%  24 pps
192.36.148.206 
194.68.128.50   stockholm.mbone.ebone.net 
     |     ^      ttl   67      941/2368 = 40% 236 pps    87/237  = 37%  23 pps
     v     |      hop  -47 s  12018/31284= 38% 226 pps  1271/3188 = 40%  23 pps
193.148.15.2   
192.87.106.102  broodjeham.surfnet.nl 
     |     ^      ttl   68      360/1639 = 22% 163 pps    26/150  = 17%  15 pps
     v     |      hop   46 s   4815/22054= 22% 159 pps   429/1917 = 22%  13 pps
193.63.94.99    mbone.ulcc.ja.net 
     |     ^      ttl   69       98/1477 =  7% 147 pps     9/124  =  7%  12 pps
     v     |      hop -166 s   1284/19880=  6% 144 pps   117/1488 =  8%  10 pps
193.63.105.99   mbone.mcc.ja.net 
     |     ^      ttl   70        2/420  =  0%  42 pps     1/115  =  1%  11 pps
     v     |      hop   56 s      3/4739 =  0%  34 pps     2/1371 =  0%   9 pps
193.63.108.100  noc.dl.ja.net  
     |     ^      ttl   71        0/332  =  0%  33 pps     0/114  =  0%  11 pps
     v     |      hop   15 ms     1/3978 =  0%  28 pps     0/1369 =  0%   9 pps
138.253.134.19  mbone.liv.ac.uk 
     |     ^      ttl   72        1/290  =  0%  29 pps     1/114  =  1%  11 pps
     v     |      hop  241 s      1/3738 =  0%  27 pps     1/1369 =  0%   9 pps
138.253.32.15   ss10-15.eeng.liv.ac.uk Not forwarding
     |      \__   ttl   73          1            0 pps       113         11 pps
     v         \  hop  -42 ms       8            0 pps       1368         9 pps
138.253.32.15   138.253.32.15
  Receiver      Query Source

=============================================================================
Jonathan Evans
Department of Electrical Engineering and Electronics
The University of Liverpool                     E-Mail: [email-masked]
PO Box 147                                      Fax: (+44)-(0)151-794-4540
LIVERPOOL   L69 3BX                             Tel: (+44)-(0)151-794-2000
United Kingdom (UK)                                                  Ext.4609
=============================================================================

---

From: Denis DeLaRoca (310) 825-4580 <[email-masked]>
Date: Mon, 11 Nov 96 14:50 PST

On Fri, 8 Nov 1996 15:28:45 +0000 GMT,
   "Mr J.C. Evans" <[email-masked]> said:
>    * * *        138.253.32.15    All Multicast Traffic     From 131.136.234.10
>      v      /     hop -241 s     ---------------------     -------------------
>      |     ^      ttl   32     1221/1602 = 76% 160 pps     2/261  =  1%  26 pp
>      v     |      hop   54 ms 15955/21066= 76% 152 pps    19/3485 =  1%  25 pp

And I keep seeing very high pkt loss rates on the bbnplanet.net routers.
Right now receiving the Stanford Channel the mtrace path through
paloalto-mbone1.bbnplanet.net (192.42.110.249) shows a pkt loss
rate of 85%.

-- Denis

---

From: Bill Fenner <[email-masked]>
Date: Mon, 11 Nov 1996 17:43:19 PST

>    The problem is that an outgoing LAN interface on
>    one router will most likely have a packet count <= to an incoming LAN 
>    interface packet count on another router because there may be many 
>    forwarders on the LAN for different sources and groups.

That's very true.  However, this would show up as negative packet loss,
since hop N+1 receives more packets than hop N sends.  The unexplained
loss attributed to bugs is positive loss, and often occurs across tunnels.

For example:

128.167.252.196 collegepk-mbone1.bbnplanet.net 
     v     ^      ttl   71      170/935  = 18%  93 pps     0/261  =  0%  26 pps
199.94.207.2    cambridge1-mbone1.bbnplanet.net 

Unless collegepk-mbone1 is doing some kind of priority queueing that
places my traffic above everyone else's, I find it hard to believe that
there's an 18% loss rate on the tunnel but 0% loss for my traffic.

  Bill