Annex D02 Circuit Switching Fundamentals Flashcards
Advantages of Circuit Switching
Users have exclusive use of that specific circuit’s entire bandwidth
No congestion
No channel access delay
Low variance and end to end delay
Circuit Switching
Process of setting up and keeping open a physical circuit between 2 or more users until the connection is terminated
Disadvantages of Circuit Switching
Due to dedicated channels, CSN can be expensive
Slight delay in establishing connection due to overhead required to make a connection through numerous switchboards
Inefficient use of bandwidth
Switchboard
Provide capability to connect one telephone line to any other within a network, alleviating the need for multiple P2P circuits
Trunk Circuit
Trunk is a communication line between two switching systems
Trunked circuit is when a call is placed across a trunk
P2P circuit
Dedicated connection directly between 2 telephones w/0 aid of a switchboard
Loop Circuit
Loop circuit connects a telephone to a switchboard
Long Local
Telephone set residing at a different site than the switchboard
Switchboard Code
Uniquely identify each switchboard within a circuit switching network
Global Block Numbering Plan
Incorporates all services into a joint network
IDs a unique service managed block of unit and subscriber numbers for each military branch
IDs databases and sub networks within the blocks of numbers
Simplifies network mgmt through the standardization of assignable NATO codes, area codes, and switchboard codes
Structure of Global Block Numbering Plan (GBNP)
3 digit area code
4 digit switch code
3 digit subscriber code
Call Routing
Method by which a switchboard routes traffic across trunks to other switchboards
Deterministic Routing
Traffic is sent to one route at a time via programmed routing tables
Alternate Routing
Provide a path for calls to travel through should the primary route fail
Switchboard Office
Central location that provides comm service to subscribers with the same office code switch (switch code)
