 the error detection and correction schemes. Increasing intelligence of the devices attached to the network The use of data transfer between and among devices on the network has moved many of the processing functions to the desktop. Because the processing is now being conducted at the local device, as opposed to using dumb terminals and a single host processor, the capacity to move the information around the network must meet the demands of each attached device. Increased functionality must be met with increases in the bandwidth allocation for these devices. Improved transmission facilities The days of dirty or poor-quality transmission lines required the use of overcorrecting protocols such as X.25 and SNA. Because the network now performs better, a newer transmission capability is needed. The need to connect LANs to Wide Area Networks (WANs) and the internetworking capabilities Today's users want to connect LANs across the boundaries of the wide area, unshackling themselves from the bounds of the LAN. The users demand and expect the same speed and accuracy across the WAN that they have on the local networks. Therefore, a new transport system to support the higher- speed connections across a wider area was needed. The LAN-to-WAN internetworking works fine in a simple point-to-point (PTP) arrangement, except that the network is dynamic, and the ability to connect to multiple sites concurrently must be robust enough to meet this new need. Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. PCUSN-to-SGSN Interface (Gb) Chapter 9 The Significance of Frame Relay The network was originally brought up through the older analog transmis- sion techniques, which have been addressed several times. As an analog transmission system, the network was extremely noisy and produced a sig- nificant amount of network errors and data corruption. This element was mos