The Fast Local Internet Protocol (FLIP) is a communication protocol for LAN and WAN, conceived for distributed applications. FLIP was designed at the Vrije Universiteit Amsterdam to support remote procedure call (RPC) in the Amoeba distributed operating system.[1]
Comparison to TCP/IP
In the OSI model, FLIP occupies the network layer (3), thus replacing IP, but it also obviates the need for a transport layer (4) protocol like TCP.
Layers of functionality in OSI, TCP/IP, and FLIP.[1]
| Layer |
OSI |
TCP/IP |
FLIP
|
| 7 |
Application |
User-defined |
User-defined
|
| 6 |
Presentation |
User-defined |
Amoeba Interface Language (AIL)
|
| 5 |
Session |
Not used |
RPC and Group communication
|
| 4 |
Transport |
TCP or UDP |
Not needed
|
| 3 |
Network |
IP |
FLIP
|
| 2 |
Data Link |
E.g., Ethernet |
E.g., Ethernet
|
| 1 |
Physical |
E.g., Coaxial cable |
E.g., Coaxial cable
|
Properties
FLIP is a connectionless protocol designed to support transparency (with respect to the underlying network layers of the OSI model: 2. data link and 1. physical), efficient RPC, group communication, secure communication and easy network management. The following FLIP properties helps to achieve the requirements of distributed computing:[1]
- FLIP identifies entities with a location-independent 64-bit identifier called Network Service Access Points (NSAPs). An entity can, for example, be a process; contrary to the IP protocol where an IP address identifies a host.
- FLIP uses a one-way mapping between the “private” address, used to register an endpoint of a network connection, and the “public” address used to advertise the endpoint.
- FLIP routes messages based on NSAP (transparency).
- FLIP discovers routes on demand.
- FLIP uses a bit in the message header to request transmission of sensitive messages across trusted networks.
See also
References
