Description: This octet string represents the current protocol stack configuration supported by the agent, encoded as a bit string. Each protocol stack is represented by a single bit. When the value of a bit = 1, it indicates that the protocol stack on the agent represented by that bit is supported; when zero, the protocol stack is not supported. The number of octets in the string is always integer multiple of the octet. The first protocol stack will encode in the least significant bit of the first octet. Current, only IP Stack(bit 0) and IPX Stack(bit 1) were defined, all other bits should be zero.