Path: utzoo!utgpu!watmath!att!ucbvax!CS.UCL.AC.UK!J.Crowcroft From: J.Crowcroft@CS.UCL.AC.UK (Jon Crowcroft) Newsgroups: comp.protocols.tcp-ip Subject: Re: trace route to OZ Message-ID: <8907282200.AA06660@ucbvax.Berkeley.EDU> Date: 24 Jul 89 12:51:34 GMT References: <8907241234.AA03375@jvnca.csc.org> Sender: daemon@ucbvax.BERKELEY.EDU Organization: The Internet Lines: 65 Sergio, et al >The link between JvNC and JANET is provided by *one* cisco router in our >end, connected through a 56kbps link to an x.25 switch in London. The >"nsfnet-relay" gateway is a SUN connected to the x.25 switching system. not quite according to ja, its a microvax connected to the x.25 switch...it will be a sun someday soon, possiblyu onm a 'null' ethernet with a cisco - still all under negotiation/decision... sorry about the misinformation on two cisco's - I was anticipating what *will* be the setup at ULCC >The *very* high delay seems to be mostly due to the x.25 switch (the >satellite delay only accounts to approximately 500 msec). In the case >of our link to NORDUnet, which is also satellite, we use a cisco router >at each end and we get a delay of approximately 600msec (average). There >are discussions to add a cisco router at the JANET end in order to reduce >the delay. yep, the x.25 switch + the uVax ahave pretty appalling performance this is due to the window of 2, limit of 1 on number of X.25 VCs the switch/uVax can support, and 128 byte X.25 packet size amongst other things...(this from john Andrews who manages the nsfnet-relay machine). >I ran ping to 128.86.8.6 and to 128.86.8.1. The first address is the address >of the "nsfnet-relay" in England, while the second one is the address of >the cisco router at JvNC. Note below the round trip delays and packets >lost for each. if i use my defense path (ucl - rsre - (different satellite path)- bbn - nsfnet backbone - jvnc - ulcc), i get similar effects, although exaggerated: Mon Jul 24 13:42:56 BST 1989 ---128.86.8.6 PING Statistics---- 17 packets transmitted, 11 packets received, 35% packet loss round-trip (ms) min/avg/max = 1760/3483/6300 ----128.86.8.1 PING Statistics---- 11 packets transmitted, 10 packets received, 9% packet loss round-trip (ms) min/avg/max = 1140/1291/1479 >We have two Technical Reports (TRs) describing the connection between JvNC >and JANET and between JvNC and NORDUnet. These two TRs are, at this point >drafts and are being "certified". For more information on either of these >international links, please send mail to "nisc@nisc.jvnc.net". will do, thanks for info... (now of course none of this has anything to do with OZ anymore, or my traceroute which was via our *defense* path - has nayone got a traceroute for the original "furthest telnet" path from OZ to scandinavia?) jon