The Connection Capacity Validation function validates and limits the configuration of Diameter connections to better ensure the configuration does not violate the Connection Count or Reserved Ingress MPS capacity limitations of the DA-MP servers that handle connections in real time.
Validation of the number of Connections and Reserved Ingress MPS occurs in response to changes to the configuration of Connections and Capacity Configuration Sets. Such changes reduce the available connection capacity and must be validated before they can be allowed. (Actions that increase Connection capacity rather than reduce it do not require validation.)
Connection Capacity Validation has no direct impact on the operation of any given DA-MP at run time or on IPFE servers. See Connections.
The following definitions apply in this document:
- Target Set
- A collection of DA-MP servers, any one of which the IPFE server can select to establish a Floating IPFE Diameter connection.
- Non-overlapping Target Set
- A Target Set where DA-MPs do not appear in any other configured Target Set.
- Overlapping Target Sets
- If any single DA-MP appears in more than one Target Set, then those Target Sets overlap the DA-MP, sharing its capacity resources.
Connection Capacity Validation behaves according to the following general principles:
- The weighting of DA-MPs within a Target Set is assumed to be equal for the purposes of all connection configuration validations.
Any non-equal weighting of DA-MPs within a Target Set (achieved through IPFE server configuration) is of no consequence to Connection Capacity Validation at configuration time.
- Over-configuration of both Connection Counts and Reserved Ingress MPS is possible in certain circumstances. No alarms or other active notifications are generated.
- For a system having no Floating IPFE Connections, no over-configuration can occur under any circumstances.
- For a system having one or more Target Sets that do not overlap each other, no over-configuration can occur (with the possible exception of upgrading an already over-configured system).
- For a system having two or more Target Sets that overlap each other in any way, over-configuration can occur because the application does not prevent configuration changes when overlapping Target Sets are involved.
- Diameter and Connection Capacity Validation prevent or do not prevent configuration changes under the following conditions:
- Diameter does not prevent connection configuration changes that involve the DA-MPs in overlapping Target Sets. The complexities of overlapping Target Sets make it difficult to determine over-configuration conditions when a diameter routing with overlapping Target Sets is near or at capacity. If there are also non-overlapping Target Sets, prevention of changes affecting non-overlapping Target Sets is still enforced.
- When only a single non-overlapping Target Set is involved, diameter routing prevents connection configuration changes that cause the Target Set's capacity to be exceeded.
- When there are no Target Sets involved at all - meaning there are no Floating IPFE Connections, only Fixed Connections - diameter routing prevents connection configuration changes that could cause the individual DA-MP hosting the subject Fixed Connection to exceed its capacity.
- The TS#: Floating IPFE Connection Reserved Ingress MPS value (percent) is applied to a DA-MPs total Engineered Ingress MPS. The TS#: Floating IPFE Connection Reserved Ingress MPS value is effectively a scaling factor on the total Reserved Ingress MPS that can be configured for a DA-MP, encompassing the contributions of both Floating IPFE and Fixed Connections.
- When dealing with a non-overlapping Target Set, the configuration capacity of the constituent DA-MPs can be thought of as pooled. Even though Floating IPFE Connections are typically considered to be evenly-distributed across all the DA-MPs in the Target Set (within a non-overlapping Target Set), capacity from one DA-MP can be borrowed and loaned to another DA-MP for the purposes of validating capacity changes. (This has no effect on the actual distribution of Floating IPFE Connections by the IPFE server.)
This situation can occur if the number of Fixed Connections varies significantly among DA-MPs in the non-overlapping Target Set. In that case, much of one DA-MP's capacity is taken up by Fixed Connections, which means there is less room for Floating IPFE Connections. But if another DA-MP in the non-overlapping Target Set has fewer Fixed Connections, it has more room for Floating IPFE Connections. The capacity on the DA-MP with fewer Fixed Connections can be used for Floating IPFE Connections.
TS#: Floating IPFE Connection Reserved Ingress MPSBecause only the Client Diameter Connections are configured with non-zero Reserved Ingress MPS,
TS#: Floating IPFE Connection Reserved Ingress MPS values (Scaling Factor) greater than 50% introduce the potential for a DA-MP to accept sufficient Floating
IPFE Connections that could result in the total ingress MPS processed by the DA-MP (including ingress MPS on non-
IPFE Connections) exceeding the DA-MP's
Engineered Ingress MPS rating.
- If only Floating IPFE Connections have non-zero Reserved Ingress MPS defined, and non-IPFE Connections have a zero Reserved Ingress MPS, the configuration restriction of the Scaling Factor = 50% enables the system to behave optimally.
- If non-IPFE Connections have non-zero Reserved Ingress MPS defined, then the maximum Reserved Ingress MPS available for all DA-MP Connections is limited by scaled Engineered Reserved Ingress MPS of the DA-MP.
Therefore, the Scaling Factor does in fact limit the total Connection Reserved Ingress MPS on a DA-MP. The intended deployment is that all Fixed Connections have a Reserved Ingress MPS value of zero so the Scaling Factor value of 50% affects only IPFE Connections.
Assumptions and Limitations
Connection Capacity Validation has the following assumptions and limitations:
Over-Configuration Considerations
Connection Capacity Validation has the following over-configuration considerations:
- Over-configuration of both Connection Counts and Connection Reserved Ingress MPS is possible and explicitly allowed when overlapping Target Sets are present.
- Running a release earlier than version 5.0, which is already over-configured in some way, remains over-configured after upgrade to version 5.0 or later.
- There are no alarms or other active notifications generated by the system to indicate Connection Count or Connection Reserved Ingress MPS over-configurations.
- View the Connection Capacity Dashboard page to check the state of the current Connection/DA-MP configuration. This is a passive notification.
- Over-configuration has no direct impact on the behavior of the DA-MP software when establishing connections. The Connection Capacity Validation feature is a configuration-only feature; the logic used by the DA-MPs to determine if any given Connection establishment request can be honored is unaffected by Connection Capacity Validation updates.
The ability for a DA-MP to run traffic in excess of the scaled engineered Ingress MPS value is unaffected by Connection Capacity Validation updates.
- Systems having a Scaling Factor of 50% before upgrade retains the 50% value after upgrade. In older systems, this Scaling Factor was not used in configuration validation. It is possible for an older system to be over-configured immediately after upgrade, with no change in configuration.
Look at the GUI page on tab Connection Reserved Ingress MPS Table to see if the Maximum Reserved Ingress MPS (for the capacity), Total Fixed Connection Reserved Ingress MPS, Total Fixed Connection Reserved Ingress MPS, and Floating Connections Reserved Ingress MPS columns show any over-configuration.
