Multitech 810-FX, 810 MVP210, 810-SS MVP210, 410 manual IP Statistics

Chapter 6—Using the Software

IP Statistics

UDP versus TCP. (User Datagram Protocol versus Transmission Control Protocol). UDP provides unguaranteed, connectionless transmission of data across an IP network. By contrast, TCP provides reliable, connection‐ oriented transmission of data.

Both TCP and UDP split data into packets called “datagrams.” However, TCP includes extra headers in the datagram to enable retransmission of lost packets and reassembly of packets into their correct order if they arrive out of order. UDP does not provide this. Lost UDP packets are irretrievable; that is, out‐of‐order UDP packets cannot be reconstituted in their proper order.

Despite these disadvantages, UDP packets can be transmitted faster than TCP packets—as much as three times faster. In certain applications, like audio and video data transmission, the need for high speed outweighs the need for verified data integrity. Sound or pictures often remain intelligible despite a certain amount of lost or disordered data packets (which comes through as static).

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