Transport Layer 3-5 Transport vs. Network layer! Network layer: logical communication between hosts! Transport layer: logical communication between processes ' relies on and enhances network layer services 12 kids in Ann’s house sending letters to 12 kids in Bill’s house:! Hosts = houses! Processes = kids. In computer networking, the transport layer is a conceptual division of methods in the layered architecture of protocols in the network stack in the Internet protocol suite and the OSI model.The protocols of this layer provide host-to-host communication services for applications. It provides services such as connection-oriented communication, reliability, flow control, and multiplexing.
![Difference between network layer and transport layer Difference between network layer and transport layer](/uploads/1/2/5/5/125516420/977552521.jpg)
The TCP/IP Guide - Network Layer (Layer 3)Please Whitelist This Site?I know everyone hates ads. But please understand that I am providing premium content for free that takes hundreds of hours of time to research and write. I don't want to go to a pay-only model like some sites, but when more and more people block ads, I end up working for free.
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At the bottom, and add this string: '@@ tcpipguide.com^$document'. Then just click OK.Thanks for your understanding!Sincerely, Charles KozierokAuthor and Publisher, The TCP/IP Guide. 991Network Layer (Layer 3)(Page 1 of 2)The third-lowest layer of the OSIReference Model is the network layer. If the data link layeris the one that basically defines the boundaries of what is considereda network, the network layer is the one that defines how internetworks(interconnected networks) function. The network layer is the lowestone in the OSI model that is concerned with actually getting data fromone computer to another even if it is on a remote network; in contrast,the data link layer only deals with devices that are local to each other.While all of layers 2 through 6 inthe OSI Reference Model serve to act as fences between thelayers below them and the layers above them, the network layer is particularlyimportant in this regard.
It is at this layer that the transition reallybegins from the more abstract functions of the higher layerswhichdon't concern themselves as much with data deliveryinto the specifictasks required to get data to its destination. The, which is related to the networklayer in a number of ways, continues this abstraction transitionas you go up the OSI protocol stack.
Network Layer FunctionsSome of the specific jobs normallyperformed by the network layer include:. Logical Addressing: Every device thatcommunicates over a network has associated with it a logical address,sometimes called a layer three address. For example, on the Internet,the Internet Protocol (IP) is the network layer protocol and every machinehas an IP address. Note that addressing is done at the data link layeras well, but those addresses refer to local physical devices. In contrast,logical addresses are independent of particular hardware and must beunique across an entire internetwork. Routing: Moving data across a series ofinterconnected networks is probably the defining function of the networklayer. It is the job of the devices and software routines that functionat the network layer to handle incoming packets from various sources,determine their final destination, and then figure out where they needto be sent to get them where they are supposed to go.
I discuss routingin the OSI model more completely in this topic on, andshow how it works by way of an. Datagram Encapsulation: The network layernormallymessages received from higher layers by placing them into datagrams(also called packets) with a network layer header. Fragmentation and Reassembly: The networklayer must send messages down to the data link layer for transmission.Some data link layer technologies have limits on the length of any messagethat can be sent. If the packet that the network layer wants to sendis too large, the network layer must split the packet up, send eachpiece to the data link layer, and then have pieces reassembled oncethey arrive at the network layer on the destination machine.
A goodexample is. Error Handling and Diagnostics: Specialprotocols are used at the network layer to allow devices that are logicallyconnected, or that are trying to route traffic, to exchange informationabout the status of hosts on the network or the devices themselves.1If you find The TCP/IP Guide useful, please consider making a small Paypal donation to help the site, using one of the buttons below. You can also donate a custom amount using the far right button (not less than $1 please, or PayPal gets most/all of your money!) In lieu of a larger donation, you may wish to. Thanks for your support!Donate $2Donate $5Donate $10Donate $20Donate $30Donate: $-(Version Date: September 20, 2005Charles M. All Rights Reserved.