Microsoft File Sharing SMB Protocol

In the beginning … (b4 dos) Application BIOS diskvideo BIOS ( basic input output system ) Provided procedures with which applications could read/write to complicated devices. Serial ports, disk drive, keyboard, mouse, etc.

DOS Application BIOS diskvideo DOS Although applications could choose between BIOS and DOS or use both, most applications migrated to DOS.

NETBIOS Application disk DOS NETBIOS redirector NIC Server An API to enable network access to disk drives

NETBEUI NETBIOS Extended User Interface Application disk DOS NETBIOS IMPROVED redirector NIC Server Netbeui (Netbeui) A protocol which supported a better set of functions, e.g. an improved API through NETBIOS.

NETBIOS extended Services have to be registered. Clients need a mechanism of resolving the machine serving the resource. Two typical means of solving this problem. –Broadcast: announce and negotiate –Point-to-point: have a central server handle both registration and resolution

Session service –connection-oriented kind of contact –a means for client to be informed if connection fails Datagram –connection-less service NETBIOS extended

Support from other protocols NETBIOS NetbeuiTCP/IP IPX NETBIOS was made to run over other protocols so applications could run in both Novell networks and TCP/IP networks.

SMB NETBIOS NetbeuiTCP/IP IPX SMB An enhancement to Netbios to allow for protocol dialects, password access and resource permissions.

Typical Interaction Client Server Which protocol dialect? Version 1.2 User dgame password xyz Login granted File thisfile Key to access thisfile

Workgroup vs Domain Client Server A Resource 1 Server B Resource 2 Client verifies access rights with each server.

Workgroup vs Domain Client Server A Resource 1 Server B Resource 2 Client verifies access rights with domain controller. Domain Controller First verify access rights Then access resource