> For the complete documentation index, see [llms.txt](https://gsm.learn-telecom.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://gsm.learn-telecom.com/system-information-messages/system-information-2bis-si-2bis.md).

# System information-2bis(SI-2bis)

RACH control and BCCH extension on neighbor cells

![](https://1516040574-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2Fg081KOVSE5kjkOj8LvCP%2Fuploads%2FUwxPAlbpzzCDty7KE3Jg%2Fimage.png?alt=media\&token=13d27510-1a69-4fb2-b08c-94ec1d8792bf)