Why is BGP considered an Application and not a routing protocol

FrankGuthrieFrankGuthrie Senior MemberMember Posts: 245
Doesn't BGP advertise networks (network command under the BGP process) the same as other routing protocol, why is it considered an application? Is it because it uses Layer 4 TCP?

Comments

  • networker050184networker050184 Went to the dark side.... Mod Posts: 11,962 Mod
    It's just semantics really. It's definitely a routing protocol.
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  • FrankGuthrieFrankGuthrie Senior Member Member Posts: 245
    It's just semantics really. It's definitely a routing protocol.

    That's what I thought, but some also say it's an application, why is that?
  • networker050184networker050184 Went to the dark side.... Mod Posts: 11,962 Mod
    It's an application, but what routing protocol isn't? It runs on a computer providing a service. I don't think to be considered an application it has to use TCP/UDP.
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  • phantasmphantasm Senior Member Member Posts: 995
    BGP is considered an application because it runs on top of the Application Layer and utilizes TCP 179. OSPF is protocol number 89 and runs on top of the Transport Layer. Conversely, EIGRP is protocol number 88 and also runs on top of the Transport Layer.

    Since BGP runs at the Application layer it relies on an underlying protocol for connectivity.
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  • FrankGuthrieFrankGuthrie Senior Member Member Posts: 245
    phantasm wrote: »
    BGP is considered an application because it runs on top of the Application Layer and utilizes TCP 179. OSPF is protocol number 89 and runs on top of the Transport Layer. Conversely, EIGRP is protocol number 88 and also runs on top of the Transport Layer.

    Since BGP runs at the Application layer it relies on an underlying protocol for connectivity.

    How deos OSPF run over the TRansport Layer. EIGRP uses RTP, so thaht I understand, but not OSPF...
  • networker050184networker050184 Went to the dark side.... Mod Posts: 11,962 Mod
    It's the IP protocol number tells the router what type of packet to expect. The TCP/IP stack is just a model, not everything fits into it perfectly.

    Really TCP or UDP has nothing to do with something being an application anyway. Does your word processor use UDP or TCP?
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  • Dieg0MDieg0M Network Engineer Member Posts: 861
    BGP is a routing protocol.
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  • bharvey92bharvey92 Senior Member Member Posts: 419
    I agree with Diego, it's a routing protocol, I've never come across any documentation that has suggested otherwise.
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  • Node ManNode Man Senior Member Member Posts: 668 ■■■□□□□□□□
    +1 semantics

    Perhaps people might argue that its not a routing protocol because it does not auto discover. But it is a routing protocol.
  • FrankGuthrieFrankGuthrie Senior Member Member Posts: 245
    Thank you for your answers.
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