You need to think in terms of "Inbound" and "Outbound". The Adaptation sits between Session Manager and the other server, such as an SBC, and makes changes based on the direction in relationship to Session Manager. You can find this information in the SysMgr Help:
fromto: If set to true, the adaptation modifies From and To headers of the message. If omitted or set to any other value, From and To headers are not modified.
multipartMIMEsupported (MIME): (Optional) This adaptation applies to the egress processing only. If the parameter is present and set to no, then multipart MIME message bodies will be stripped on egress from Session Manager. If the multipart MIME message contained an SDP message body, it will be inserted as the only message body in the outgoing message. If omitted or set to any other value, message bodies will not be modified.
EGRESS Domain Modification Parameters
[ul]
[li] overrideDestinationDomain ( can be abbreviated to odstd): {parameter #1 if not named}, replaces the domain in Request-URI, To header (if administered), Refer-To header, and Notify/message-summary body with the given value for egress only.[/li]
[li] overrideSourceDomain ( can be abbreviated to osrcd): replaces the domain in the From header (if administered), P-Asserted-Identity header and calling part of the History-Info header with the given value for egress only.[/li]
[/ul]
INGRESS Domain Modification Parameters:
[ul]
[li] ingressOverrideDestinationDomain ( can be abbreviated to iodstd): replaces the domain in Request-URI, To header (if administered), and Notify/message-summary body with the given value for ingress only.[/li]
[li] ingressOverrideSourceDomain ( can be abbreviated to iosrcd): replaces the domain in the From header (if administered), P-Asserted-Identity header and calling part of the History-Info header with the given value for ingress only.[/li]
[/ul]
Let's say Company has an SBC that is connected to a Provider. The provider wants to see the IP address of their router (10.10.10.1) while Company wants to use the domain
company.com. You would then set up your Adaptation something like this and assign it to the SBC SIP Entity
Adaption Name: SIP Provider
Module Name: DigitConversionAdapter
Module Parameter Type: Name-Value Parameter
fromto = true
iodstd = company.com
iosrcd = company.com
odstd = 10.10.10.1
osrcd = 10.10.10.1
To change digits in the "TO" and "FROM" fields you enter that information in the sections marked
Digit Conversion for Incoming Calls to SM and
Digit Conversion for Outgoing Calls from SM depending on if you are converting digits sent to the provider (FROM SM) or from the provider (TO SM).
I hope that helps.