Distance-Vector Routing Protocols for Networks with Unidirectional Link

W e first introduce a simple distance-vector proto-col f o r routing in networks having unidirectional links. The protocol can be seen as a n adaptation for these net-works of the strategy as used in the popular RIP proto-col. T h e protocol comprises two m a i n algorithms, one f o r collecting “from ” information, and the other one for generating and propagating ((to ” information. How-ever, the traditional RIP approach has been a ‘(busy” one because of the periodic sending of routing informa-t ion euen after the network has reached a stable state. W e make fur ther improvements o n the simple proto-col t o get a message-thrifty variant. Routing informa-t ion message i s sent only when there i s a change t o the topology or when a lank changes cost and only those affected entries need t o be sent around. 1