The VMSC will request the information needed for it to deliver the Short Message to its recipient by sending a Send_Info_for_MT_SMS message to the VLR. The VLR will then instigate a page request, or subscriber search, for the destination subscribers Mobile Subscriber ISDN Number (MSISDN), and return the result to the VMSC. Since a typical deployment sees the VLR being co-located with the MSC, this message flow is usually internal to the platform. Should the page or search for the subscriber fail, the VLR will indicate the failure cause to the VMSC, which will abort the Short Message delivery procedure and return the failure to the SMSC (see the Failed Short Message delivery section below). If the page of the handset was successful, the VMSC will then send to the SMSC indicating successful delivery. The GMSC component of the SMSC passes the result of the delivery attempt to the Service Centre. In the case of successful delivery, the delivered text message will be removed from the Store and Forward Engine (SFE) and, if requested, a delivery report sent to the text originator. If the delivery failed, the SMSC invokes a retry procedure to periodically make further attempts at delivery; additionally, it may register with the HLR to receive a notification when the B-Party becomes available for Short Message delivery in the future (see the Failed Short Message delivery section below).