Anynet (MPTN) vs TCP/IP: Pros & Cons

Problems with Areas Anynet (MPTN)

As users started to use Anynet, flaws began to appear, particularly when large amounts of data needed to be transported. Typical problems included disconnecting sessions and slow performance. These problems were not readily apparent on local networks; they were much more prevalent when the timing between the host and device is delayed. In recent tests we tried to establish a connection across the Internet. We were able to get a session started using a PC with the NS/Router, however within three minutes of working with this session it disconnected. We also tried connecting with a remote controller, which used the same protocol. We were able to vary on the controller, however the terminals on the controller never established a connection.

TCP/IP Makes its Entrance

In recent years IBM has focused their development on TN5250. With the arrival of V4R2 (and later PTFs to support older versions) IBM supported TN5250e and TN3270e. This enhanced TCP/IP support enabled the AS/400 and 3270 hosts to support device naming and SCS printer support. For the first time, users could really take advantage of native TCP/IP support on these hosts. IPDS was also supported directly with TCP/IP using PPD/PPR (a special protocol developed for this specific purpose). Recent versions of Client Access (Client Access Express) contain support for native TCP/IP only, providing proof that IBM’s direction is to provide better support for native TCP/IP on these host computers.

Advantages of TCP/IP over Anynet (MPTN)

Because TN5250 and TN3270 use native support on the system, they do not require as many CPU cycles to make use of it. TN5250e and TN3270e do not have the timing limitations that SNA has, therefore these protocols can be used over the Internet with no problem. IBM has realized this and that is one of the reasons that Client Access Express supports SSL encryption, to enable users who want to connect using the Internet a way to do so without encountering security issues. Recent tests show that IPDS printing takes three times the number of TCP/IP packets to print the same document via SNA than via native TCP/IP. Imagine the effect on the performance of a 56K frame relay circuit supporting a number of IPDS printers using SNA!

IBM 5494 Controller has been Withdrawn

The IBM 5494 Controller was discontinued at the end of 1999, and now both Perle and NLynx are developing TN5250 controllers of their own. BOScom clearly leads the field with its e-Twin@x Controller, since it uses the same TCP/IP protocol as the very stable and field-tested BOSâNOVA TCP/IP TN5250e emulator, which has been installed and working on hundreds of thousands PCs since 1997. For experience and state-of-the-art technology, choose BOScom.

For more information on BOScom's e-Twin@x Controller click here.
To order a demo click here!