Networking What are the basic concepts of networking? Three classes MPP (Massively parallel processor network) LAN (Local area network) WAN (Wide area network) Common paradigm Messages/packets are transferred between a sender and a receiver Header Request, reply, acknowledge request, acknowledge reply Info Actual data being transferred

Networking Performance measures Checksum Ensures reliability (no scrambling of message) Performance measures Bandwidth – maximum rate of data propagation Transmission Time – size of message/bandwidth Time of Flight – time for first bit of message to arrive at the receiver Transport Latency – time of flight + transmission time Sender Overhead - adding of headers Receiver Overhead – stripping of headers (may cause an interrupt), is generally larger than sender overhead

Connecting Computers What techniques are used to interconnect computers for MPPs? Where do you connect the network within the computer? I/O bus vs. memory bus MPPs are the only type of network that usually connect to the memory bus Interconnection Media Twisted pair Coaxial cable Fiber