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At which OSI layer does the RIP protocol operate in?

I tried to analyze all dynamic protocols in terms of OSI Layers, and I found RIP is at the application layer; however, I don't understand what the need is for RIP is to reach the application layer.

I need more clarity on what the application name which RIP uses is. Perhaps in the application layer or something.

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    I'm sorry, but the question is too unclear right now. What part of RIP's operation are you asking about? How are you going to use this information?
    – This
    Feb 18 '14 at 8:49
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    RIP itself is used by layer 3, sent on layer 4 (udp) and implemented via layer 7 @MikePennington I think the question is: on which layers is RIP implemented?
    – Bulki
    Feb 18 '14 at 11:36
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    @Bulki, the question shouldn't require mind-reading. We need the OP to clarify which part of RIP he is asking about because as you mention, there are multiple ways to slice the question
    – This
    Feb 18 '14 at 11:42
  • @ Mike and @ Bulki - I tried to analyze all dynamic protocol working nature in OSI Layers, I found RIP is on application layer, however i don't understand what is the need of rip to reach application layer. Could you give me a more clarity what is the application name which RIP uses in application layer or something. Thank you Feb 18 '14 at 12:34
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    Rip daemon/service/... sends broadcast/multicast packets, to advertise the networks connected to the device (router). After receiving data from neighbours, the application (rip 'daemon'/service/whatever) has to calculate the new routing table, and set it on the device (router).
    – mulaz
    Feb 18 '14 at 12:43
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I think you're getting confused on how the OSI model plays into the routing. It's just a model, nothing more, nothing less. RIP works at layer 3 and sends routing information across the network.

I found RIP is at the application layer, however I don't understand what the need for RIP is to reach the application layer.

RIP isn't at the application layer because no application can use it (within reason) and the application layer needs it to find the route to the proper device. RIPs only function is to distribute routing updates. It only tells neighboring routers about routes it knows about.

I need more clarity on what the application name which RIP uses is.

RIP, in and of itself, is an application, but it supports the network layer of the OSI model. There are daemons you can download on your computer, like routed, that allow servers to talk to other RIP processes. Just try to understand the theory that each application/daemon supports a different purpose (or layer) of the OSI model.

I hope this doesn't add anymore confusion...

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  • Perhaps you could try to integrate or respond to what Mulaz said in your answer. As a side comment, I'm personally starting to dislike the whole idea of these OSI protocol mapping questions. OSI protocol mapping questions should be discussed more in Network Engineering Meta
    – This
    Feb 18 '14 at 19:56
  • @MikePennington I agree. The OSI construct made it much more difficult for me (personally) to understand how routing is supposed to work, and truth be told, I still have a hard time equating the OSI model to anything practical. OSI questions are starting to pop up more and more these days.
    – Ryan Foley
    Feb 18 '14 at 20:08
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    @MikePennington Maybe we should write a "ghost" question and answer it ourselves. Then we can always point to it when someone asks. The questions are always variations on the same theme, and I doubt they will go away.
    – Ron Trunk
    Feb 19 '14 at 2:41
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    @MikePennington I'm sorry, but I have to disagree on this one. These questions are all about network-theory and are a major part of understanding how networks work. I do think it's a valid question (when asked clearly and to the point) for this forum.
    – Bulki
    Feb 19 '14 at 7:04
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    some people have never met a vague question they can't answer ;-)
    – This
    Feb 19 '14 at 8:41
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RIP is an Application Layer protocol. The application that is using the protocol is the RIP routing process / application on each router.

An application layer protocol will still rely upon lower layers (Transport, Network, Data Link and Physical) to help deliver the Application data. In this case, the RIP data is the contents of a router's routing table. If you examine a packet capture from Wireshark or nmap, you will see that in order to deliver the RIP data, it will rely upon UDP, with port number 520 which is used the RIP routing process, at the Transport layer.

As for the Network layer, a standard IPv4 or IPv6 header is used. In the case of IPv4 and RIPv1 the destination address is the broadcast address, 255.255.255.255. In the case of and IPv4 and RIPv2 the destination address is a multicasting address, specifically 224.0.0.1.

As for a formal executable name, the RIP routing process may be called something different on different routers. However these processes/applications are the ones sharing data, hence RIP is an Application Layer protocol.

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Ripv2 & RIPng are layer 3 protocols and these protocols generate and multicast(224.0.0.9) updates every 30 seconds by default.

These update packets are carried by the transport layer protocol UDP and use UDP port 521.

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  • Hi Satheesh , Thanks for your Answer, Unfortunately its not correct it seems, will wait for some one to answer with justification .... Feb 18 '14 at 8:35
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    @user3146180, RIP was not designed with the OSI model in mind. So it doesn't fit neatly into any layer.
    – Ron Trunk
    Feb 18 '14 at 11:34
  • RIPv2 uses UDP port 520, but RIPng uses UDP port 521.
    – Pue-Tsuâ
    May 18 '16 at 1:11
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All IGP (Interior gateway protocols) routing protocols works at layer 3. External BGP works at layer 4, while internal works at layer 3.

  1. Physical Layer - Deals with hardware network devices, i.e laptops, mobile phones, desktops. Layer 1 is known to be a collision domain, Layer 1 PDU (protocol data unit is bits).

  2. Data/link layer - This layer concerns with layer 2 switches, broadcast domains, VLANS, STP, VTP. The protocol data unit of this layer is called frames.

  3. Network Layer - This is when routing occurs, most routing protocols works at this layer. This is also known as the IP layer, where VLANS communicate. The PDU for this layer is known as packets.

  4. Transport layer - Transport layer deals with TCP and UDP ports, these is where the packets from layers 3 are sent to their destination ports. It is important to remember that TCP is a connection-oriented protocol while UDP is connection-less oriented protocol (non guranteed delivery of data). The PDU for this layer is datagrams.

  5. Session layer - Session layer is where the packets are encapsulated from being decapsulated from layer 3. This layer deals with multiple server side programming languages where you can create software-based applications and convert them into ->

  6. The Presentation layer - This layer is about the client-side codes you see on your web browser, or when you do a right-click and view the source, these are mainly HTM/CSS/Javascript codes that allows you to view your ->

  7. The Application layer - This is where the GUI (Graphical user interface) translates the HTML/CSS codes from layer 6 to this layer. What you see on your web browser is the front end GUI. Layer 5,6,7 PDU is called message.

I hope these answer all OSI-related questions.

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  • This does not answer the question he asked though.
    – This
    Feb 18 '14 at 15:12

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