1.3 Teorías relacionadas al tema
1.3.2 Bases teóricas de la satisfacción de los usuarios Historia satisfacción de los usuarios
Transport
Introduction to the feature
This feature provides the GSM Packet Abis specific functionality to support IPv4 protocol over the Ethernet and TDM interfaces of the SBTS (user and control plane) as well as the SBTS remote management (management plane).
3.18.1.1 Benefits
End-user benefits
This feature does not affect the end-user experience.
Operator benefits
This feature provides a more cost efficient transport network for the GSM Abis interface which results in OPEX and CAPEX savings.
3.18.1.2 Requirements
Hardware requirements
This feature requires Flexi Multiradio 10 System Module (FSMF).
3.18.1.3 Functional description
The feature uses the IPv4 transport functions introduced by the feature SR000589:
IPv4/IPv6 Transport Stack and provides functionalities to support GSM Packet Abis interface user and control plane of the SBTS as well as the SBTS management plane.
Both Packet Abis over Ethernet and Packet Abis over TDM are supported.
This feature provides the following GSM applications:
• GSM user plane transport support based on NSN-RTP/UDP/IPv4 (compliant with 3GPP TR43.903)
• GSM control and management plane support based on SCTP/IPv4 (compliant with RFC4960)
IP addressing
In the simplest configuration, all U/C/M-plane applications are bound to one single IP interface address. Applications can be bound to interface IP addresses (including alias IP addresses) or to virtual IP addresses. It is possible to configure up to four IP
addresses:
• GSM user plane circuit switched domain
• GSM user plane packet switched domain
• GSM control plane
• GSM OMUSIG management plane
The IP addresses are configured in the following way:
• binding of the C/U-Plane applications is done based on the information sent by BSC using Abis O&M interface
• binding of the GSM OMUSIG M-plane applications is configured via SBTS O&M interface
Traffic marking
Traffic in the U/C/M-plane is marked by the GSM RAT application:
• DSCP values for GSM OMUSIG M-plane are configured using SBTS O&M interface
• DSCP values for U/C/M-Plane are sent by BSC using Abis O&M interface (these values overwrite the DSCP value configured for GSM OMUSIG M-plane)
Maximum transmission unit (MTU) size:
To determine maximum packet size, the Path MTU Discovery (PMTUD) technique is used. This functionality is required to minimize fragmentation and avoid packet loss.
PMTUD is automatically applied to U-plane IP addresses.
Bandwidth congestion control
The feature implements the bandwidth utilization measurement as well as the post processing of these measurements. The post processing is performed based on committed information rate (CIR) and utilization thresholds received from BSC.
Delta t scheduling
This feature uses delta t scheduling provided by the feature SR000402: BTS QoS Support for Terminated and Routed Traffic. This mechanism enables to establish the maximum age of a packet. Before sending, the transport software checks the age field and drops outdated packets.
IP header compression
This feature uses ML/MC-PPP and header compression support provided by the feature SR000176: ML-PPP termination.
Packet Abis delay measurement
This feature implements a UDP-based round-trip time (RTT) measurement which measures the RTT of GSM U-plane packets between SBTS and BSC. The RTT measurements are provided to BSC upon request.
Counters
This feature implements GSM specific counters for bandwidth utilization, SCTP, RTP and UDP. These counters are accessible via BSC.
3.18.1.4 System impact
Interdependencies between features
This feature requires the following features:
• SR000589: IPv4/IPv6 Transport Stack
• SR000402: BTS QoS Support for Terminated and Routed Traffic
• SR000176: ML-PPP termination
• SR000954: SBTS Common Transport
Related features:
• SR000918: SBTS Basic Performance Management
• SR000920: SBTS Fault Management Impact on interfaces
This feature has no impact on interfaces.
Impact on network and network element management tools
This feature has no impact on network management or network element management tools.
Impact on system performance and capacity
This feature has no impact on system performance or capacity.
3.18.1.5 SR000397: IPv4 based Packet Abis Transport management data
For information on alarm, counter, key performance indicator, and parameter documents, see Reference documentation.
Alarms
There are no alarms related to this feature.
BTS faults and reported alarms
There are no BTS faults related to this feature.
Measurements and counters
There are no measurements or counters related to this feature.
Key performance indicators
There are no key performance indicators related to this feature.
Parameters
Table 52: New parameters lists parameters introduced with this feature.
Table 52 New parameters
Full name Abbreviated name Managed object
IUA acknowledge timer iuaAckTimerOmuSig BTSSCC
Management plane DSCP for OMUSIG mPlaneDscpOmuSig BTSSCC
Management plane local IP address for OMUSIG
mPlaneLocalIpAddressOmuS ig
BTSSCC
Bundling enabled sctpBundlingEnabledOmuSig BTSSCC
Heartbeat interval sctpHbIntervalOmuSig BTSSCC
SCTP maximum payload size sctpMaxPayloadSize BTSSCC
Maximum retransmission association sctpMaxRetransAssocOmuSi g
BTSSCC
Maximum retransmission path sctpMaxRetransPathOmuSig BTSSCC
Minimum SCTP port sctpPortOmuSig BTSSCC
Initial retransmission timeout sctpRtoInitOmuSig BTSSCC
Maximum retransmission timeout sctpRtoMaxOmuSig BTSSCC
Minimum retransmission timeout sctpRtoMinOmuSig BTSSCC
Selective acknowledge period sctpSackPeriodOmuSig BTSSCC
User-CS supervision packet timer value ucsSupervisionPktTimerValue BTSSCC
UDP maximum datagram size udpMaxDatagramSize BTSSCC
User-PS supervision packet timer value upsSupervisionPktTimerValu e
BTSSCC
Feature activation flag for IPv4 based Packet Abis TRS
actIpV4BasedPktAbTrs TNL
3.18.1.6 Sales information
Table 53 Sales information
BSW/ASW License control in network element
ASW Pool license