Acronyms Cellular

GPRS - (General Packet Radio Service)
GPRS is used in more that 200 countries and is used in 2G and 3 G cellular networks. Packet orientated mobile data service that offers best effort service. GPRS extends the GSM packet circuit switched data capabilities and offers the following services

• Internet Access (Always on)
• MMS (Multimedia Messaging Service)
• PoC/PTT (Push to talk over cellular)
• Instant Messaging and Presence
• Internet Applications using WAP (Wireless Application Protocol)
• P2P (Point to Point service inter-networking with IP

GPRS connection is established by leveraging its APN (Access Point Name). APN is used to define services such as SMS, MMS, WAP, and internet communication to services such as WWW and email.

VLR - (Visitor Location Register)
A database of the subscribers who have roamed into the domain of another MNO (Mobile Network Operator/MSC (Mobile Switching Center).

Data stored in the VLR Database include:

• IMSI (the subscriber's identity number)
• Authentication data
• MSISDN (Mobile Subscriber's phone number)
• GSM services that the subscriber is allowed to access
• Access point (GPRS) subscribed
• The HLR address of the subscriber

Responsibilities of the VLR are:

• Inform the HLR that a subscriber has arrived in the particular area covered by the VLR
• Track where the subscriber is within the VLR area (location area) when no call is ongoing
• Authorize which services the subscriber is eligible
• Allocate roaming numbers during the processing of incoming calls
• Purge the subscriber record if a subscriber becomes inactive while in the area of a VLR. The VLR deletes the subscriber's data after a fixed time period of inactivity and informs the HLR
• Delete the subscriber record when a subscriber explicitly moves to another, as instructed by the HLR.

Carrier Grade IPv6 (CGv6)

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HLR/VLR

VLR - (Visitor Location Register)
A database of the subscribers who have roamed into the domain of another MNO (Mobile Network Operator/MSC (Mobile Switching Center).

Data stored in the VLR Database include:

• IMSI (the subscriber's identity number)
• Authentication data
• MSISDN (Mobile Subscriber's phone number)
• GSM services that the subscriber is allowed to access
• Access point (GPRS) subscribed
• The HLR address of the subscriber

Responsibilities of the VLR are:

• Inform the HLR that a subscriber has arrived in the particular area covered by the VLR
• Track where the subscriber is within the VLR area (location area) when no call is ongoing
• Authorize which services the subscriber is eligible
• Allocate roaming numbers during the processing of incoming calls
• Purge the subscriber record if a subscriber becomes inactive while in the area of a VLR. The VLR deletes the subscriber's data after a fixed time period of inactivity and informs the HLR
• Delete the subscriber record when a subscriber explicitly moves to another, as instructed by the HLR.

HLR - (Home Location Register)
Central database that contains details of each Mobile Subscriber that is authorized to use the GSM core network. HLRs stores the information of every SIM card issued by the mobile network operator. SIM cards have a unique identifier called an IMSI which is the primary key to each HLR record. MSISDN (Telephone Number) information is also kept within the SIM and is also primary key in the HLR database.

Data stored in the HLR using the IMSI record

• GSM services that the subscriber has requested
• GPRS settings authorizing the subscriber to the access packet services
• Current location of subscriber (VLR and serving GPRS support node/SGSN).
• Call divert settings applicable for each associated MSISDN.

The main responsibility of the HLR is to manage the movement of SIMs and MS.

Process used by the HLR to manage the movement of MS and SIMs

• Manage the mobility of subscribers by means of updating their position in administrative areas called location areas.
• Send the subscriber data to a VLR or SGSN when a subscriber first roams onto another MNO's network
• Broker between the G-MSC or SMSC and the subscriber's current VLR in order to allow incoming calls or text messages to be delivered
• Remove subscriber data from the previous VLR when a subscriber has roamed away from the visiting MNO's network

GPRS

GPRS - (General Packet Radio Service) 
GPRS is used in more that 200 countries and is used in 2G and 3 G cellular networks. Packet orientated mobile data service that offers best effort service. GPRS extends the GSM packet circuit switched data capabilities and offers the following services
-Internet Access (Always on)
-MMS (Multimedia Messaging Service)
-PoC/PTT (Push to talk over cellular)
-Instant Messaging and Presence
-Internet Applications using WAP (Wireless Application Protocol)
-P2P (Point to Point service inter-networking with IP

GPRS connection is established by leveraging its APN (Access Point Name). APN is used to define services such as SMS, MMS, WAP, and internet communication to services such as WWW and email.

Quick Notes - MPLS Advertise Labels

When using MPLS and restricting what routes have labels ensure to run "no mpls ldp advertise-labels" before adding the restriction. I have seen that if you do not run the command above you will get labels advertised for all routes.

Here is an example:

config>mpls ip
config>no mpls ldp advertise-labels
config>mpls ldp advertise-labels for 10
config>access-list 10 permit 150.8.0.0 0.0.255.255
config-if>mpls ip

GSM and CDMA

GSM and CDMA


GSM and CDMA Continued

Cellular Networks

SONET/SDH

Embedded Event Manager - Default Route

Here is a EEM Scenario Question:

Provide a solution that provides failover capabilities from the primary link to the backup link and failback capabilities from the backup link to the primary link. You must send a syslog message stating "Failed over to the Backup Link" during failover and a syslog message "Failed Back to the Primary Link" when failing back.

Requirements:
- You cannot use IP SLA
- You cannot use dynamic routing on R1
- You cannot modify the current routing configuration on R2 and R4
- You cannot use static floating routes on R1