---
title: Constructing an alternative metadata exchange endpoint
description: You can embed virtual server ID information into a security token service (STS) metadata exchange endpoint or a SAML and WS-Federation metadata exchange endpoint.
component: pingfederate
version: 13.1
page_id: pingfederate:developers_reference_guide:pf_construct_alt_metadata_exchange_endpoint
canonical_url: https://docs.pingidentity.com/pingfederate/13.1/developers_reference_guide/pf_construct_alt_metadata_exchange_endpoint.html
llms_txt: https://docs.pingidentity.com/pingfederate/llms.txt
docs_for_agents: https://developer.pingidentity.com/build-with-ai/docs-for-agents.md
revdate: July 5, 2022
section_ids:
  about-this-task: About this task
  steps: Steps
  example: Example:
  example-2: Example:
  example-3: Example:
---

# Constructing an alternative metadata exchange endpoint

You can embed virtual server ID information into a security token service (STS) metadata exchange endpoint or a SAML and WS-Federation metadata exchange endpoint.

## About this task

This process is useful for scenarios where partners prefer to retrieve metadata by sending one query parameter such as`PartnerSpId` or `PartnerIdpId`, instead of two query parameters such as `PartnerSpId` or `PartnerIdpId` and `vsid`.

## Steps

1. Construct a JSON object containing a key-value pair of the virtual server ID by using the following format. `\{"vsid":"<VirtualServerIdValue>"}`

   ### Example:

   For example, if the virtual server ID is `Engineering`, the JSON object is `\{"vsid":"Engineering"}`.

2. Base64url-encode the JSON object.

   ### Example:

   For example, if the JSON object is `\{"vsid":"Engineering"}`, the base64url-encoded value is `eyJ2c2lkIjoiRW5naW5lZXJpbmcifQ`.

   Learn more about base64url in [RFC 4648](https://datatracker.ietf.org/doc/html/rfc4648#autoid-10).

3. Insert the base64url-encoded value prefixed with a forward slash into the metadata exchange endpoints, described as follows:

   * Federation metadata endpoint (`/pf/federation_metadata.ping`)

     Between `/pf` and `/federation_metadata.ping`.

   * STS metadata endpoint (`/pf/sts_mex.ping`)

     Between `/pf` and `/sts_mex.ping`.

     ### Example:

     For example, if the base64url-encoded value is `eyJ2c2lkIjoiRW5naW5lZXJpbmcifQ`, the metadata exchange endpoints embedding with the virtual server ID are:

   * Federation metadata endpoint

     `/pf/eyJ2c2lkIjoiRW5naW5lZXJpbmcifQ/federation_metadata.ping`

     Example: https\://idp.example.com:9031/pf/eyJ2c2lkIjoiRW5naW5lZXJpbmcifQ/federation\_metadata.ping?PartnerSpId=sp.example.org

   * STS metadata endpoint

     `/pf/eyJ2c2lkIjoiRW5naW5lZXJpbmcifQ/sts_mex.ping`

   Example: https\://idp.example.com:9031/pf/eyJ2c2lkIjoiRW5naW5lZXJpbmcifQ/sts\_mex.ping?PartnerSpId=sp.example.org