Hybrid Networks Running Multiple Platforms
In this web page the word platform is
used to describe different computing architectures or hardware platforms.
It is also important to remember that different platforms are also likely
to run different operating systems.
Presently, we outline some issues of intercommunication across platforms.
Gateways. Now we look at making use of gateways, particularly software based gateways between networks to ensure connectivity. These discussions will focus on the following.
SNA. SNA was developed by IBM in the 1970s to allow interconnection of incompatible systems with a layered architecture. In particular, they were motivated to get their own variety of systems, such as PCs and mainframes to interact.
The main components of SNA include the following.
Current implementations are called APPN - Advanced Peer to Peer. APPN supports two types of nodes.
SNA architecture requires that a session between a client and a server is established before any data can be transferred. SNA is a more complex protocol than TCP/IP.
It can also be implemented as Communications Manager for OS/2 and SNA Server for Microsoft's Windows NT or Windows 2000. SNA Server can als obe configured for dial in connections and VPN - Virtual Private Networking. This has been recently renamed Host Integration Server by Microsoft. There is also a Linux SNA.
Samba. Samba has been developed for Windows and UNIX/Linux interconnectivity and interaction. Samba was created by reverse engineering Microsoft's SMB protocol which has been their so called core protocol for file sharing. The goal was to make a UNIX server look like a Windows server to Microsoft clients. This goal is attained to greater and greater extents with each new release.
Samba allows UNIX/Linux and Microsoft systems to intercommunicate through the CIFS - Common Internet File System which is based on SMB. CIFS provides the following four services.
Shared resources can be password protected. NetBIOS name resolution can be provided either by broadcast messages or by using a NetBIOS name server such as WINS.
Samba is made up of several programs. There are two main components or daemons that provide the services listed above.