Which two statements about the PMM-DETACHED state are true? (Choose two.)

Question

Options

• AThe Mobile Subscriber and SGSN contexts hold no valid location or routing information for
• BThe Mobile Subscriber location is known in the 3G SGSN with an accuracy of a serving RNC.
• CThe serving RNC tracks the location of the Mobile Subscriber.
• DA 3G SGSN cannot reach the Mobile Subscriber location because the location is unknown.
• ESignaling towards the HLR is needed if the 3G SGSN does not have an MM context for this
• FThe Mobile Subscriber performs a routing area update if the routing area changes.

• A
  92% (35)
• B
  3% (1)
• F
  5% (2)

Explanation

PMM-DETACHED is the state where the Mobile Subscriber has not performed a GPRS attach, meaning no MM context exists in the SGSN and neither the network nor the subscriber holds valid location or routing data - confirming A. Because the SGSN has no MM context and no location information, it has absolutely no way to page or contact the subscriber, making D correct as well.

Why the distractors are wrong:

• B & C describe PMM-CONNECTED behavior, where an active RRC connection exists and the serving RNC actively tracks the MS location.
• E describes what happens during a GPRS Attach procedure (transitioning out of DETACHED), not a characteristic of the DETACHED state itself.
• F describes PMM-IDLE behavior; a detached subscriber does not send routing area updates - it must perform a full GPRS Attach first.

Memory tip: Think of PMM-DETACHED as being "off the grid" - the network is completely blind to the subscriber's existence and location. PMM-IDLE = "known city, unknown street"; PMM-CONNECTED = "known building, known room"; PMM-DETACHED = "no idea if they even exist on the network."

No community discussion yet for this question.