An IP Fundamentals Question.

elderkaielderkai Packet MonkeyMember Posts: 279
Hey guys. I'm reading the ROUTE FLG and I have a question. In the first chapter when it starts transitioning to RIP, it mentions the cons of RIPs broadcasts. It discusses the process of how other devices process the RIP broadcast. It quotes:
RIPv1 uses a 255.255.255.255 broadcast address, so all devices, including PCs andservers, must process the update packet. They perform the checksum on the Layer 2 packet and pass it up
their IP stack. IP sends the packet to the User Datagram Protocol (UDP) process, and UDP checks to see
whether RIP port 520 is available. Most PCs and servers do not have any process running on this port and
discard the packet.

I understand everything there, except for being confused at the UDP part. I thought that things like RIP, ICMP, and other protocols like that had their own IP protocol number and it didn't mess with TCP or UDP. Can someone elaborate on this a little for me? ^.^

Comments

  • MrBrianMrBrian Grind time, gotta eat Member Posts: 520
    No, you're correct, some of the routing protocols use UDP/ TCP, and some don't..

    RIP > UDP

    BGP > TCP

    EIGRP > IP protocol 88

    OSPF > IP protocol 89

    I dug up this thread from the past that has some discussion around this, here ya go:
    http://www.techexams.net/forums/ccna-ccent/72495-lan-vs-wan-protocols-rip-ospf-eigrp-frame-relay-hdlc-ppp.html#post587654
    Currently reading: Internet Routing Architectures by Halabi
  • elderkaielderkai Packet Monkey Member Posts: 279
    Oh okay. Thank you. ^.^
  • MrBrianMrBrian Grind time, gotta eat Member Posts: 520
    Check out (if you haven't already) some good tcp/ip books. There's some massive guides out there that are good to reference if you ever have any confusion. Personally I have the TCP/IP guide by Kozierok for reference.

    In addition, I'd suggest "TCP/IP Illustrated Vol 1: The Protocols" by Stevens. It's a great book and you can get it used on the cheap.. I think they just revamped it to a more current release too. I have the older one that's from the late 90's (I believe, but not sure). Some of the info is outdated, but you'll recognize those parts and just skip em, but the beauty is that a lot of it is the same.

    Anyways, I would say give that book a read through and it will mesh a lot if you're fairly fresh from CCNA. I don't know your situation though, maybe you've got it down.. but yea I read through that book shortly after CCNA and it really tied a lot of things down for me, it was awesome. Taking a pause from my early ROUTE studies to go through that book really allowed me to go down the NP path faster.. (even though it's taking me awhile, but full time college is to blame for that)
    Currently reading: Internet Routing Architectures by Halabi
  • elderkaielderkai Packet Monkey Member Posts: 279
    MrBrian wrote: »
    Check out (if you haven't already) some good tcp/ip books. There's some massive guides out there that are good to reference if you ever have any confusion. Personally I have the TCP/IP guide by Kozierok for reference.

    In addition, I'd suggest "TCP/IP Illustrated Vol 1: The Protocols" by Stevens. It's a great book and you can get it used on the cheap.. I think they just revamped it to a more current release too. I have the older one that's from the late 90's (I believe, but not sure). Some of the info is outdated, but you'll recognize those parts and just skip em, but the beauty is that a lot of it is the same.

    Anyways, I would say give that book a read through and it will mesh a lot if you're fairly fresh from CCNA. I don't know your situation though, maybe you've got it down.. but yea I read through that book shortly after CCNA and it really tied a lot of things down for me, it was awesome. Taking a pause from my early ROUTE studies to go through that book really allowed me to go down the NP path faster.. (even though it's taking me awhile, but full time college is to blame for that)
    Would you suggest those books over Routing TCP/IP? I got my CCNA back in June and I'm just using the time I have free from school to study for the CCNP. I plan to finish Bryant's ROUTE course and the book by December 10th. I'm hoping at least. Then that'd give me Christmas break to lab.
  • MrBrianMrBrian Grind time, gotta eat Member Posts: 520
    elderkai wrote: »
    Would you suggest those books over Routing TCP/IP? I got my CCNA back in June and I'm just using the time I have free from school to study for the CCNP. I plan to finish Bryant's ROUTE course and the book by December 10th. I'm hoping at least. Then that'd give me Christmas break to lab.

    Good question. I've only read the OSPF and EIGRP sections of Routing TCP/IP so I can't speak of its actual coverage of general tcp/ip.. That book goes into great detail about certain protocols, whereas TCP/IP Illustrated is more foundational/fundamental. Both books are pure gold though.

    I think Routing TCP/IP is more geared towards routing only (hence the name), but the other book brings the OSI model to life. It was like for me, during the CCNA I was drilling what every layer stood for, and knew what protocols "lived" at certain layers, but didn't really have a firm grasp of the flow of things. Going through TCP/IP Illustrated really made it all make sense. I'd really recommend it. It gets you into looking at protocol headers and what contents are in the headers, etc.

    You don't need to study the book necessarily, but just read through it, it'll put it in perspective more, about how data is passed down the stack, and then sent out on the wire, or air, for that matter.

    7.50$ used for a book from '93, but it sure gets it done. The more updated one is llike 40-50$ though
    TCP/IP Illustrated,Vol. 1: The Protocols (Addison-Wesley Professional Computing Series): W. Richard Stevens: 9780201633467: Amazon.com: Books
    Currently reading: Internet Routing Architectures by Halabi
  • elderkaielderkai Packet Monkey Member Posts: 279
    Sweet. I'll definitely pick it up or see if I can buy a digital copy to start reading faster. I would love a better view on the flow of data and being able to look at IP headers and make conclusions. ^.^ Thanks a bunch, man.
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