Asynchronous Transfer Mode Flashcards
Draw a diagram of ATM
What does ATM switching do?
Enables the cost-efficient, high-speed transfer of data, voice, and video on internetworks
Why is ATM necessary?
There is currently an 80/20 traffic reversal in internetworks, leading to the necessary integration of LAN and WAN (such as VPNs, Voice over IP).
ATM helps to reduce costs, improve performacnce, and reduce downtime.
What type of traffic does ATM support?
Any, including separate or mixed streams, delay-sensitive and non-delay sensitive, and low to high speeds
How does ATM improve performance?
- use of large buffers (provides QoS for multimedia)
- virtual circuit queues
- rate scheduling
- identification of network congestion
How does ATM reduce downtime?
Via fast rerouting and support of redundant components (processors, port and trunk interfaces, UPS)
What does UPS stand for?
Uninterrupted Power Supply
Where is ATM often used?
- large public network infrastructures
- high-speed backbone networks that offer Frame Relay services
What makes ATM a good global packet standard?
- Supports all traffic types
- Works on WAN and LAN environments, so can internetwork between them smoothly
What is another term for STM?
Synchronous Transfer Mode = traditional multiplexing
What’s the difference between ATM and STM?
- STM uses a fixed frame size and assigns fixed time slots in periodic frames to individual channels
- ATM uses a header to identify individual channels and their destinations. Fixed time slots are assigned based on bandwidth capacity and QoS requirements (dynamic)
Why is ATM “asynchronous”?
Because the arrival rate of user data is random.
What is the ATMF?
ATM Forum, that publishes implementation agreements for ATN network interfaces and approves UNI versions.
What’s the difference in ATM specifications for private and public networks?
Public networks should use fiber optic, T3 or T1 UNIs. Private is less restrictive, and can use UTP UNIs, for example.
What is a UNI?
User to Network Interface
