tcpip stack or subsystem

[Shivkumar]

Dear Sirs/Madam;

What is the tcpip stack ? I have seen IBM uses the tcpip stack or subsystem terminology on their mainframe and aix ? How HP has implemented tcpip technology in HPUX 11i ?

Thanks,
Shiv

[Mel Burslan · Accepted solution]

tcpip stack terminology comes from the stack like figurative representation of OSI 7 layer model of network communications.

if you go to this page and scroll to the bottom, you will see the stack like figure and data always goes from top and leaves from the top, i.e. Last In First Out principle. That makes up for the word stack

http://www.webopedia.com/quick_ref/OSI_Layers.asp

I have seen it being used as tcpip stack or tcpip subsystem as well myself. The terminology is interchangable and does not have different meanings in the hpux or any unix flavor as far as I know.

[John Dvorchak]

Because TCP/IP is a public domain protocol for network communications, HPUX and others have integrated it into the base OS. Not too many years ago, before the Internet, there were propritary Nework protocals and each Vender had thier own ideas. The IBM mainframe used something called LLC or HDLC but have since then added the TCP/IP protocal "stack", meaning another part.

Since networking is now a necessity, most vendors include a network package, TCP/IP in this case, with the OS. It used to be marketed as a separate package like IBM does. I remember in the 80's seeing UNIX sold as and OS and TCP/IP as an optional added package.

[Geoff Wild]

This is a depends ?...

Example, the TCP/IP Protocol Stack is a 5 layer protocol - where the bottom 4 layers resemble the bottom 4 of the OSI model - and the top layer represents the top 3 laysers of OSI:

Application
Transport (TCP/UDP)
Network (IP)
Data Link
Physical

For more info, get the HP Certifies CSA book by Rafeeq Rehman...

Rgds..Geoff