Bandwidth Aggregation
Bandwidth reservation
Bandwidth reservation
Executive
Available bandwidth
Executive
Available bandwidth
© 2003, Cisco Systems, Inc. All rights reserved.
Choose the Configuration>System>Tunneling Protocols>IPSec>IPSec LAN-to-LAN
window and select the connection you wish to modify by choosing the Modify button. From the bandwidth policy drop-down menu, select a bandwidth policy to apply to this IPSec LAN-to-LAN connection from the drop-down list. If you do not want to select a policy here, select none. When the bandwidth reservation policy is applied to a LAN-to-LAN connection, the Concentrator automatically aggregates the bandwidth. The minimum bandwidth is applied to the tunnel rather than on a per user basis. This allows you to reserve a specific amount of bandwidth for the site-to-site connection.
In the figure, the LAN-to-LAN policy was defined with a minimum bandwidth of 384 Kbps. This policy was applied to the LAN-to-LAN tunnel configurations (only the Site B tunnel configuration is shown). Once applied, the Concentrator will aggregate 384 Kbps of bandwidth to each LAN-to-LAN tunnel.
Note If the bandwidth reservation is enabled and the administrator selects None from the LAN-to-
LAN Bandwidth Policy drop-down menu, the LAN-to-LAN tunnel contends for system wide bandwidth, a default user. If no reservation is applied and the tunnel drops, there is no guarantee that the LAN-to-LAN tunnel can reconnect if other default remote users make a connection before the LAN-to-LAN tunnel reestablishes its connection. It is suggested that, if bandwidth reservation is applied to the network, a LAN-to-LAN bandwidth reservation policy should be defined and applied.
LAN-to-LAN Bandwidth Reservation Configuration
© 2003, Cisco Systems, Inc. All rights reserved.
© 2003, Cisco Systems, Inc. All rights reserved.
Configuring bandwidth reservation alone may lead to a scenario in which high priority, high bandwidth, users are unable to connect to a congested Concentrator because of their bandwidth requirements. In this example, the Concentrator provides a feature called bandwidth aggregation. Bandwidth aggregation allows a particular group to reserve a fixed portion of the total bandwidth on the interface. (This fixed portion is known as an aggregation.) Then, as users from that group connect, each receives a part of the total bandwidth allocated for that group. When one group makes a reserved bandwidth aggregation, it does not affect the bandwidth allocated to users who are not in that group. However, other users are now sharing a smaller amount of the total bandwidth. Fewer users can connect. One can think of bandwidth reservation as pieces of a pie. Each group is assigned a slice of pie, aggregate bandwidth. As tunnels are established, each user is assigned part of the slice until the slice is completely divided. At that point, any new connections requesting a slice of the piece are refused a connection. Choose the Configuration>User Management>Groups>Bandwidth Policy>Interfaces window to assign a bandwidth aggregation. Configure the following parameters:
■ Policy—Select a bandwidth policy from the Policy drop-down menu.
■ Bandwidth Aggregation—Enter a value for the minimum bandwidth to reserve for this group and select a unit of measure.
In the figure, the executive group is assigned a bandwidth aggregation of 512 Kbps. As each executive connects, they are allocated part of the 512 Kbps aggregated bandwidth. The amount of bandwidth allocated to each executive is defined by the assigned policy. In this case, each executive reserves bandwidth of 128Kbps. Executive users are allocated bandwidth until their 512 Kbps slice of the bandwidth pie has been allocated.
Continue reading here: Remote Access Tunneling Hardware Client Mode
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