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Private Leased Line |
ATM |
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Key Difference |
Not suitable for all traffic types |
Single access connections used for data, voice, video |
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Definition |
A leased-line is the casual, informal name for a connection to the Digital data Network.
Point -to - point
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Asynchronous Transfer Mode.
Point -to - point
Point -to -multipoint |
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Quality of Services |
Real time traffic |
Selectable quality |
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Benefits |
- The private nature of the leased line networks provides inherent privacy and control benefits.
- The digital nature of leased lines also provides higher line quality than analog lines. Dedicated lines are just that.
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- meet customer requirements thus increasing bandwidth efficiency
- Provides the highest level of resilience and diversity
- Bundled routers managed (business continuity)
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Application |
point-to-point real time application |
- Packetised Voice and Video conferencing
- Large file transfers and database replications
- Corporate Internets/Extranets
- All types of IP traffic, e.g. e-mail, web browsing, FTP
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Speed |
Options for leased lines start from around :
- About 2400 bps up to 64 kbps for voice and data transmission
- From 64 kbps to 1.024 mbps which allow high speed connections between LANs
- 6/64 Kbps leased lines are useful for networks that have moderate traffic requirements such as large file transfers, between a limited numbers of sites
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Simple, fast, switching & self routing.
When purchasing ATM service, you generally have a choice of four different types of service:
- Constant bit rate (CBR): specifies a fixed bit rate. This is analogous to a leased line.
- Variable bit rate (VBR): provides a specified throughput capacity. This is a popular choice for voice and videoconferencing data.
- Available bit rate (ABR): provides a guaranteed minimum capacity but when the network is free.
- Unspecified bit rate (UBR): This is used for applications, such as file transfer, that can tolerate delays.
Higher speeds from 1.024 mbps to 155 mbps are available.
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Security |
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Similar as a lease line |
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Future |
Leased lines will continue to dominate the corporate communications market due to the huge installed base that they currently enjoy. However, their popularity will gradually decline as alternatives such as ATM: IP/MPLS continue to grow. |
Self routing switches can grow in size & speed to meet the user's future communication requirements. |
