- From: hang-tak chau <hangtak@hotmail.com>
- Date: Wed, 31 Oct 2001 17:58:33
- To: mnot@mnot.net, Paul.Hadfield@symbian.com, Matt@stimulussolutions.com.au
- Cc: http-wg@cuckoo.hpl.hp.com
Please help in this networking question. Please help! 1.) Compare and contrast a distance-vector routing algorithm like RIP and a link-state routing algorithm like OSPF. Be sure to compare and contrast each protocol's approach to routing and how each protocol exchanges routing information. Do not include information on the packet layouts (i.e., header layout, field locations, etc.) in your answer. Note that explaining how distance-vector routing works in one paragraph, and then explaining how link-state routing works in another paragraph, without tying the two discussions together, does not constitute a compare and contrast (and does not answer this question.) 2) TCP is said to be a rather inefficient transport protocol when a small amount of data needs to be exchanged (such as when a simple web page is sent) but an efficient protocol for large data transfers (such as large file transfers with FTP.) Explain why. Include technical details in your answer. 3.) Consider an IP network composed of two Class A networks (10.0.0.0/8 and 18.0.0.0/8) connected by a router, R, having interfaces 1 and 2. The IP addresses of hosts A, B, C, and D, as well as of interfaces R1 and R2, are given in the figure below. Let the Ethernet address of host A be called MAC_A, of R1 be called MAC_R1, and so forth. A B 10.0.0.1 18.0.0.1 C D | | +-----+ | | --------------------------|1 R 2|----------------------------- 10.0.0.3 10.0.0.4 +-----+ 18.0.0.7 18.0.0.8 3a) Suppose that host A has some application layer data (layer-5) to send to host B using UDP. Describe this process in detail. Specifically, explain what happens on host A at each of the five layers of the Internet Model. Assume for this question that Host A has never sent data before to Host B. Write your answer in the form of a detailed list, such that step 1 in your list is "(1) Host A's application passes its data off to the layer-4 UDP module where it is encapsulated and a UDP header is added." Be sure to include information on how MAC addresses, IP addresses and subnet masks are used by the host. Include information on the use of ARP and the use of a routing table (if necessary) in your answer. Your explanation can stop at the point when A's data reaches B's Ethernet interface; you needn't explain what happens in B's protocol stack. 3b) Using the same list format, explain the process by which host A sends some application layer data to host D. Again, your explanation can stop at the point when A's data reaches D's Ethernet interface. Assume for this question that Host A has never sent data before to the router, or to Host D. 4a.) Suppose an Ethernet switch receives a frame destined for a host located on the same ethernet segment as the source host. What does the switch do with the frame? Could there be any difference in the behavior of the switch depending on whether either or both hosts had previously sent any data? 4b.) Consider the following ethernet network consisting of two hosts, A and B, and two Ethernet switches, S1 and S2. As you can see, the network is divided into two parts, the top portion and the bottom portion, and each switch has one port attached to each part of the network. Assume the network does not implement any kind of switch level protocol such as the Spanning-Tree Algorithm. What types of problems (if any) would result from such a configuration? A | --------- | | S1 S2 | | --------- | B 5.) Assume that there are two computer systems, Host A and Host B, both running the TCP/IP protocol stack and both connected to the same Ethernet LAN. In this problem, we ask you a number of questions related to the use of TCP. 5b.) Describe, using a time sequence diagram, the opening of the TCP connection between these two systems via a three-way handshake. (Assume that Host A opens the connection to Host B.) Include information on the sequence numbers. 5b.) Lost TCP Acknowledgements do not necessarily force retransmission. Explain why. 5c.) Describe the use of the TCP checksum, including a description of the parts of the packet that it covers. 6a.) Describe the use of DLCIs in a Frame Relay network which uses PVCs (not SVCs.) 6b.) Explain how congestion control is handled in a Frame Relay network. Be sure to mention such concepts as the BECN, FECN, and DE bits. >From: Mark Nottingham <mnot@mnot.net> >To: Paul.Hadfield@symbian.com >CC: http-wg@cuckoo.hpl.hp.com >Subject: Re: Http requirements >Date: Tue, 30 Oct 2001 20:54:07 -0800 > > >FYI: > >This is discussed (somewhat sporadically) at: > http://groups.yahoo.com/group/http-compliance/ >and is also of some interest on the W3C's w3c-qa mailing list. > >(not to say that it is or isn't appropriate here as well) > >Cheers, > > >On Tue, Oct 30, 2001 at 09:39:55AM +0000, Paul.Hadfield@symbian.com wrote: > > > > Hi, > > > > I too am interested in any information about conformance test suites for > > HTTP/1.1. I've recently been involved in a client implementation, and > > found planning the conformance testing a very manual task, mainly >because I > > could locate no resource other than the RFC that listed (in brief!) >which > > RFC MUST/SHOULD clauses apply to each class of application. > > > > It's interesting to contrast this with the WAP Forum's conformance > > specifications, which are found at the end of each of their specs. > > Furthermore there's a test suite produced and administered by >OpenGroup.org > > which tests clients against each clause. I'd be very happy to discover > > that an organisation somewhere has produced a similar HTTP/1.1 client > > conformance suite. > > > > Paul Hadfield > > > > Software Engineer > > Browser Technologies > > Symbian Ltd. > > http://www.symbian.com/ > > > > > > > > > > Matt Lynch > > <Matt@stimulussolutio To: >http-wg@cuckoo.hpl.hp.com > > ns.com.au> cc: > > Subject: Http >requirements > > 30/10/01 01:03 > > > > > > > > > > > > > > G'day all, > > I'm just getting to the end of an http implementation, and am >in > > testing for conformance to the spec. I've interpreted the spec to the >best > > of my ability, and I'd like to cross reference this list against >another. > > Does anyone know the url to a document summarising the spec? This seems > > like such an academic exercise, I figured that there would be an .edu >site > > with this info... > > > > Matt Lynch > > Developer > > Stimulus Solutions > > http://www.stimulussolutions.com.au > > > > > > > > > > > > > > > > ********************************************************************** > > Symbian Ltd is a company registered in England and Wales with registered >number 01796587 and registered office at 19 Harcourt Street, London, W1H >4HF, UK. > > This message is intended only for use by the named addressee and may >contain privileged and/or confidential information. If you are not the >named addressee you should not disseminate, copy or take any action in >reliance on it. If you have received this message in error please notify >postmaster@symbian.com and delete the message and any attachments >accompanying it immediately. Symbian does not accept liability for any >corruption, interception, amendment, tampering or viruses occurring to this >message in transit or for any message sent by its employees which is not in >compliance with Symbian corporate policy. > > ********************************************************************** > > > >-- >Mark Nottingham >http://www.mnot.net/ > > _________________________________________________________________ Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp
Received on Wednesday, 31 October 2001 17:59:35 UTC