Oracle provides the following IPS package repositories for Oracle Solaris. See also Comparing Repository Content Sources.
The Oracle Solaris release repository is publicly available at http://pkg.oracle.com/solaris/release/. The release repository is updated at every Oracle Solaris GA release. For example, the release repository was updated for Oracle Solaris 11.1, Oracle Solaris 11.2, Oracle Solaris 11.3, and Oracle Solaris 11.4. Some FOSS updates are available in the release repository between Oracle Solaris GA releases. See FOSS in Oracle Solaris for more information.
Previous Oracle Solaris GA release repositories are available as file downloads from My Oracle Support (MOS) and other sites as described in How to Copy a Repository From a zip File. For example, on MOS see Where to download Oracle Solaris ISO images and Update Releases (Doc ID 1277964.1) for GA repositories. The first link under each release section is a link to download the IPS repository file for that release.
The Oracle Solaris support repository is available at https://pkg.oracle.com/solaris/support/. To access the support repository, follow the instructions in How to Install a Certificate and Key for the Oracle Solaris Support Repository. The support repository includes the content of the release repository plus fixes, including security fixes, that were made after the release repository was released.
Support Repository Updates (SRUs) are integrated into the Oracle Solaris support repository and are also available as separate repository updates that you can download from MOS or other sites as described in How to Copy a Repository From a zip File.
Updates to the support repository are released approximately monthly. Every third SRU is a CPU (Critical Patch Update) SRU with content typically more focused on security fixes. See Critical Patch Updates, Security Alerts and Third Party Bulletin for information about CPUs. SRU repositories include only packages for that SRU. While each SRU includes all fixes and enhancements that were delivered by previously released SRUs, an SRU does not contain any other SRUs. An SRU contains only one version of pkg:/entire. For best system upgrade results, integrate SRUs into your local Oracle Solaris repository monthly, either from the Oracle Solaris support repository URI or from the downloaded SRU repository files.
If you update your local repository from the Oracle Solaris support repository URI (as described in Copying a Repository From the Internet), then you receive all packages for each update. If you failed to apply an update one month but updated in a subsequent month, the missed update would still be available in your updated repository. For example, if you updated in March but not in February, you would still be able to update systems to the February update level by using one of the solutions described in Updating to a Version Older Than the Newest Version Allowed in Updating Systems and Adding Software in Oracle Solaris 11.4.
If you update your local repository from downloaded SRU files, you can only update systems to those SRU levels. For example, if you applied the January and March SRU repository updates but did not apply the February update to your local repository, you would not be able to update systems to the February SRU level. You could add the February SRU repository content to your local repository, even though you already added the March content, and then you could update systems to the February SRU level. If your repository does not contain the version of pkg:/entire for a particular SRU update, then you cannot update to that SRU level.