Transcript
V7.4 NORTEL NETWORKS CONFIDENTIAL
CDMA 2000 1xEV-DO System Overview
Course # 0890AEN
Version 01.01
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What is CDMA2000 1xEV-DO?
• CDMA2000 1xEV-DO stands for 1xRTT Evolution – Data Only—What this means is that it is an evolution from
CDMA2000 1X (IS-2000/CDMA2000) networks—Where CDMA2000 1X has both data and voice
capabilities, CDMA2000 1xEV-DO is data only (without the voice component)
• CDMA2000 1xEV-DO offers high-speed packet data rates up to 2.45 Mbps where CDMA2000 1X has a maximum data rate of 153.6 Kbps
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What is CDMA2000 1xEV-DO? (continued)
• CDMA2000 1xEV-DO is overlaid on an existing CDMA2000 1X network but requires a separate 1.25 MHz carrier and a dedicated T1/E1 backhaul from the Metro Cell to the data only radio network controller (DO-RNC)
• Shares the packet-data network with CDMA2000 1X
• CDMA2000 1xEV-DO is based on IS-856 / CDMA2000 1X is based on IS-2000
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CDMA2000 1xEV-DO components
• As CDMA2000 1xEV-DO is overlaid on an existing CDMA2000 1X network, there are many shared components
• The shared components with CDMA2000 1X are:— MetroCell— PDSN— AAA server (if not deploying AN-AAA)
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CDMA2000 1xEV-DO components (continued)
• The new components required for CDMA2000 1xEV-DO are:—Data Only Module (DOM) located in the MetroCell—Data Only Radio Network Controller (DO-RNC)
located at the central office (CO)—Data only element management subsystem
(DO-EMS) and can be co-located at the CO with the DO-RNC and BSC
—Access network authorization, authentication and accounting (AN-AAA) server (optional)
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CDMA2000 1xEV-DO components (continued)Data Only Module (DOM)
• IS-856 module added to CEM shelf in Metro Cell
• provides CDMA2000 1xEV-DO modem capability.
• performs all the encoding/decoding of the IP packets
• Requires MFRM
• supports 30 connected sessions per sector
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CDMA2000 1xEV-DO components (continued)
Data Only Radio Network Controller (DO-RNC)
• at the core of the CDMA2000 1xEV-DO network
• manages the access terminal state, handoffs and connections to the packet data network through the packet data switching node (PDSN).
• controlling the DOMs at multiple cell sites over an IP-based backhaul network
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CDMA2000 1xEV-DO components (continued)
Data only element management subsystem (DO-EMS)
• provides OA&M capability and controls the operation, administration, maintenance and provisioning (OAMP) operations for the CDMA2000 1xEV-DO radio access network (RAN).
• based on a Sun Netra 20 NEBS compliant platform and may be located at the central office (CO)
• stand-alone platform for performing OAM&P functionality within the CDMA2000 1xEV-DO network only
Sun Netra 20
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CDMA2000 1xEV-DO components (continued)
Access network authorization, authentication and accounting (AN-AAA) server
• optional requirement (as specified in IS-878) used for access terminal authentication at the beginning of a CDMA2000 1xEV-DO data session
• used for device level authentication
• terminates the point-to-point protocol (PPP) session required for terminal authentication at the beginning of a CDMA2000 1xEV-DO session
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CDMA2000 1xEV-DO components (continued)
Network upgrades from CDMA2000 1X
• Dedicated T1/E1 backhaul from the Metro Cell to the DO-RNC
• Additional 1.25 MHz carrier for data only trafficNote: More 1.25 carriers can be added for increased
users (additional DOMs need to be added for each additional CDMA2000 1xEV-DO carrier)
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Lesson 2:
The evolution to CDMA2000 1xEV-DO
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The evolution to CDMA2000 1xEV-DO
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The path to CDMA2000 1xEV-DO
CDMA2000 1X in the beginning:• CDMA2000 1xEV-DO is an
evolution from conventional IS-2000 (CDMA2000 1X) networks.
• CDMA2000 1X offers both voice and data capabilities compared to conventional CDMA (IS-95) networks (voice only)
• CDMA2000 1X high speed packet data
— Rates of up to 153.6 Kbps (144 Kbps user)
• New hardware for 3G (CDMA2000 1X):
— XCEM in Metro Cell— SCI-S and ESEL in BSC— Shasta BSN 5000 for PDSN
and HA functionality— AAA server, routers, hubs, for
data network administration
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The path to CDMA2000 1xEV-DO (continued)
Evolution to CDMA2000 1xEV-DO:• CDMA2000 1xEV-DO offers data
only capabilities compared to 1xRTT networks (voice and data)
• CDMA2000 1xEV-DO overlaid on existing CDMA2000 1x network and shares the following:
— Metrocell— PDSN— AAA server (if present)
• New components for CDMA2000 1xEV-DO
— data only module (DOM)— data only radio network
controller (DO-RNC)— data only element
management subsystem(DO-EMS)
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The path to CDMA2000 1xEV-DO (continued)
CDMA2000 1xEV-DO offers:
• High speed packet data— Rates of up to 2.45
Mbps
• Full time forward power by time division multiplexing
• No shared spectrum with other users
• No soft hand-offs in forward direction, soft hand-off in reverse
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The path to CDMA2000 1xEV-DO (continued)
Packet Data Network
The CDMA2000 1xEV-DO system does not define a new packet data network architecture.
In fact, both the CDMA2000 1xEV-DO and the CDMA2000 1X systems share the same packet data network infrastructure.
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Lesson 3:
What is CDMA20001xEV-DO?
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What is CDMA2000 1xEV-DO?
• CDMA2000 1xEV-DO (1xRTT evolution–data only) is a wireless packet data-only technology—Used for customer data applications where voice communication
is not required
• high-speed packet data support of variable rates up to 2.45 Mbps on the forward link and up to 153.6 kbps on the reverse (upload) link
• CDMA2000 1xEV-DO uses time-division multiplexing (TDM) in the forward direction, meaning there are no soft handoffs in the forward direction and only one terminal receives data from each sector at a given time
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What is CDMA2000 1xEV-DO? (continued)
• can be overlaid on an existing CDMA2000 1X network with a separate 1.25 MHz radio carrier
• CDMA2000 1xEV-DO is deployed on a Metro Cell equipped with a data-only module (DOM), a new data only radio network controller (DO-RNC), and the data-only element management server (DO-EMS).
• The CDMA2000 1xEV-DO network overlay works with the existing IS-2000 core network elements, allowing re-use of the CDMA2000 1X Metro Cell BTS (including GPS receiver, MFRM, radio antenna and duplexers), Shasta PDSN and PDSN-AAA server
• Required dedicated backhaul mechanism (T1/E1 or 10/100 BaseT ethernet) from the BTS to the DO-RNC
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Benefits of CDMA2000 1xEV-DO
• Uses less bandwidth that UMTS (1.25 MHz rather that 5 MHz)• Core network elements are shared with CDMA2000 1X meaning
cost of upgrade is minimal• No degradation of CDMA2000 1X voice calls since CDMA2000
1xEV-DO is deployed on separate 1.25 MHz carriers• As CDMA2000 1xEV-DO uses TDM, there is full time full power as
the bandwidth is not shared with other users like CDMA2000 1X
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CDMA2000 1xEV-DO requirements
• Metro Cell containing MFRMs
• dedicated T1/E1 (or 10/100 BaseT ethernet) backhaul (from Metro Cell to DO-RNC)
• separate 1.25 MHz radio carrier to support CDMA2000 1xEV-DO
• New hardware (DOM, RNC, EMS)—AN-AAA (optional)
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New CDMA2000 1xEV-DO components
The new hardware components consists of:
• Data Only Module (DOM) located in the MetroCell (CEM shelf)
• Data Only Radio Network Controller (DO-RNC) co-located at the central office (CO) with the base station controller (BSC)
• Data only element management subsystem (DO-EMS) co-located at the central office with the DO-RNC and BSC
• Access network authorization, authentication and accounting (AN-AAA) server (optional)
DOM DO-RNC
DO-EMS
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Data Only Module (DOM)
The DOM is approximately 2 inches wide and is located in the CEM shelf and provides the modem capabilities for CDMA2000 1xEV-DO
Can be deployed in any Metro Cell containing MFRM
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Data Only Module (DOM) (continued)
DOM capacity
One DOM supports up to a three sector, 1.25 MHz carrier Metro Cell
Each DOM modem supports 30 connections per sector in the forward link.
Additional DOMs need to be added for each additional CDMA2000 1xEV-DO carrier.
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Data Only Module (DOM) (continued)
Installation and commissioning
DOM installation does not negatively impact the Metro Cell service and availability. — including Metro Cell CDMA2000
1X/IS-95 service on any of the carriers not supported by the DOM in question
Customers can use the DOM Tool-kit, the CDMA Vortex application or the data-only element management subsystem (DO-EMS) to commission the DOMs.
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Data Only Radio Network Controller(DO-RNC)The data only radio network controller
(DO-RNC) is at the core of the CDMA2000 1xEV-DO network. It forms part of the access network together with the Metro Cell BTS and the IP backhaul transmission network.
The DO-RNC is a stand alone node supporting the CDMA20001xEV-DO overlay network. It manages the access terminal state, handoffs and connections to the packet data network through the packet data switching node (PDSN).
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Data Only Radio Network Controller(DO-RNC)Functions of the DO-RNC• controlling the DOMs at multiple
cell sites over an IP-based backhaul network.
• controls the sessions and air link connections of CDMA2000 1xEV-DO access terminal
• coordinates handoffs of access terminals between cells and carrier frequencies
• manages the state of the access terminal (idle or connected)
• service negotiation• paging and access channel
message termination
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Data Only Radio Network Controller(DO-RNC)The DO-RNC is located at the central
office (CO) with the base station controller (BSC) and/or BSS manager (BSM)
One DO-RNC supports from 64 to over 100 DOMs, depending on the traffic loading at the DOM. The maximum number of carriers per DO-RNC is 200.
The DO-RNC is frequency independent and can control BTSs that are operating on either 800 MHz or 1900 MHz or a combination thereof.
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Data only element management subsystem (DO-EMS) and client
DO-EMS consists of both hardware (the server) and software (the client)
provides OA&M capability and controls the operation, administration, maintenance and provisioning (OAMP) operations for the CDMA2000 1xEV-DO radio access network (RAN)
Sun Netra 20
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Data only element management subsystem (DO-EMS) and client (continued)
The DO-EMS is a stand-alone platform for performing OAM&P functionality within the CDMA2000 1xEV-DO network only
The existing BSS Manager (BSM) will have its capabilities extended to enable the recognition of the CDMA2000 1xEV-DO DOM module in a Metro Cell BTS
Each DO-EMS supports up to three DO-RNCs and approximately 200 DOMs, depending upon the network configuration.
Sun Netra 20
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Data only element management subsystem (DO-EMS) and client (continued)Client features• CDMA2000 1xEV-DO In-Field
Toolbox (similar functionality to the CDMA Vortex application)
• collecting, reporting, and managing alarms associated with the DO-RNC and DOM
• collects and stores OMs from the DO-RNC and DOM
• storing, scheduling, and distributing software downloads to the DO-RNC and DOM
• administers and manages the neighbor list for CDMA2000 1xEV-DO access terminals
Sun Netra 20
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Data only element management subsystem (DO-EMS) and client (continued)DO-EMS Serverbased on a Sun Netra 20 NEBS
compliant platform and may be located at the CO (central office). The server contains several software modules that perform the following functions:
• auto-discovery• configuration management• security management• fault management• performance management Sun Netra 20
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Data only element management subsystem (DO-EMS) and client (continued)DO-EMS Clientweb-based client runs in standard
web browsers, offering network administrators a familiar, easy-to-use interface to robust configuration, fault, and performance management tools
Provides:• Network topology views• Network database views• Active device panel• Performance statistics
administration• System administration
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Data only element management subsystem (DO-EMS) and client (continued)DO-EMS Client (continued)
Provides
• Fault management tools— alarm browser— event browser
• Management tools— MIB manager— Policy manager
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Access network authorization, authentication and accounting (AN-AAA) server
The access network authorization, authentication and accounting (AN-AAA) server is an optional requirement (as specified in IS-878) used for access terminal authentication at the beginning of a CDMA2000 1xEV-DO data session.
If operators do not deploy an AN-AAA, they may use the existing AAA Radius server currently used in the CDMA2000 1X network.
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Access network authorization, authentication and accounting (AN-AAA) server
With an AN-AAA:
• The DO-RNC authenticates access terminals.
• The DO-RNC communicates with one or more AN-AAA servers.
• The AN-AAA can act as a proxy server to determine the Radius server for an access terminal that is roaming.
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Access network authorization, authentication and accounting (AN-AAA) server
Benefits of deploying AN-AAA
• Consistent IMSI (International Mobile Subscriber Identity) for billing
• Control of authentication
• PDSN protection
• Theft of 1xEV-DO access
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Hybrid access terminal
A new hybrid access terminal is required to support voice on IS-2000 systems and packet data services on both IS-2000 and IS-856 systems. The hybrid access terminal is required to operate in both IS-856 and IS-2000 modes and is capable of monitoring both the CDMA2000 1xEV-DO and CDMA2000 1X systems simultaneously.
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Typical 1 XEV-DO System Deployment
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Lesson 4:
Introduction to IS-856
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Introduction to IS-856
The TIA/EIA Engineering Committee TR-45 (Mobile and Personal Communications Systems) has developed a standard called IS-856 as a companion to the already existing IS-2000 standard. These standards are the next generation of wireless standards after the second-generation (2G) CDMA standards, known as IS-95.
The IS-856 (CDMA2000 1xEV-DO) air interface standard provides high rate packet data services between the access terminal and the access network.
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IS-856 Protocol LayersThe CDMA2000 1xEV-DO protocol layering does not conform to
the open system interconnection (OSI) seven layer model.
OSI seven layer protocol IS-856 seven layer protocol
Layer 1: Application layer Layer 1: Application layer
Layer 2: Presentation layer Layer 2: Stream layer
Layer 3: Session layer Layer 3: Session layer
Layer 4: Transport layer Layer 4: Connection layer
Layer 5: Network layer Layer 5: Security layer
Layer 6: Data Link Layer Layer 6: MAC layer
Layer 7: Physical layer Layer 7: Physical layer
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IS-856 Protocol Layers
The CDMA2000 1xEV-DO air interface protocol layers (continued)
IS-856 seven layer protocol
Description
Layer 1: Application layer Message routing, RLP, flow controlLayer 2: Stream layer Multiplex various application streamsLayer 3: Session layer Establishes/configures data sessionsLayer 4: Connection layer Establishes and manages radio
connectionLayer 5: Security layer Authentication and encryptionLayer 6: MAC layer Data rate controlling and schedulingLayer 7: Physical layer Adaptive modulation and code
spreading
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IS-856 Protocol Layers
The CDMA2000 1xEV-DO air interface protocol layers
IS-856 seven layer protocol
Description
Layer 1: Application layer Message routing, RLP, flow controlLayer 2: Stream layer Multiplex various application streamsLayer 3: Session layer Establishes/configures data sessionsLayer 4: Connection layer Establishes and manages radio
connectionLayer 5: Security layer Authentication and encryptionLayer 6: MAC layer Data rate controlling and schedulingLayer 7: Physical layer Adaptive modulation and code
spreading
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IS-856 Physical Layer
Major improvements to the physical layer from IS-2000:— Higher data rates : utilizes
turbo coding in forward and reverse directions
— Dynamic turbo encoding rates : Turbo codes have been shown to perform better for high rate data services
— Source identification : no source identification in reverse direction
— Higher order modulation : adaptive modulation
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IS-856 Physical Layer (continued)
Major improvements to the physical layer from IS-2000:— Channelization :
forward link channels time-multiplexed (no Walsh codes) not code multiplexed
— Each access terminal receives full power for their time rather than sharing power across time
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IS-856 Physical Layer (continued)
Major improvements to the physical layer from IS-2000:— Forward link transmit
power : transmits at maximum available power all the time
— IS-856 channel structure : forward direction = time division multiplexed, reverse direction = code division multiplexed
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IS-856 Forward link
Forward traffic flow travels from the packet data network/internet through the CDMA2000 1xEV-DO radio access network to the user.
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IS-856 Forward link
Forward channel structure
• The access network transmits the following forward link channels at full power in time-multiplexed fashion. At a fixed position in every physical layer slot, these channels are transmitted:— pilot channel— medium access control— control channel— traffic channel
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IS-856 Forward link
Forward channel slot structureIn forward direction, there are
two types of slots:• Active Slot: When access
network has either control information or user traffic to send, it sends this information along with MAC and pilot channel in a time-multiplexed fashion.
• Idle Slot: When access network does not have control information or user traffic to send, it still sends pilot and MAC channels in their given time at full power and does not transmit control/traffic information.
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IS-856 Forward link
Paging/control channel slot structure
• access terminal (handset) monitors both the CDMA2000 1xEV-DO and CDMA2000 1X network simultaneously
• Paging channels for both CDMA2000 1xEV-DO and CDMA2000 1X are staggered
• If paging channels collide, IS-856 assigns a different paging slot
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IS-856 Forward link
Forward frame structure
• Physical layer code spread across 1.25 MHz – identical to IS-95/2000
• IS-856 only has one physical channel and MAC, control and traffic channels are time multiplexed on the single channel
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IS-856 Forward link
Fat pipe scheduling• using a large radio
spectrum as a shared wireless link
• all terminals in sector share wireless link
• access network schedules transmission of packets over shared link
• packets are time division multiplexed not code multiplexed
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IS-856 Reverse link
Reverse traffic flow travels from the user through the CDMA2000 1xEV-DO radio access network to the packet data network/internet .
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IS-856 Reverse Link
• reverse link of IS-856 is quite similar to the reverse link in an IS-2000 system
• reverse link power control performed same asIS-2000 (except at 600 times per second)
• access network sends power control command in every slot for all connected ATs
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IS-856 Reverse Link
• IS-856 and IS-2000 similarities— power control and soft handoff supported— BPSK modulation on I & Q (data & pilot) carrier to reduce
peak to average ratio— distinct user PN sequence for source ID— data rates from 9.6 to 153.6 Kbit/s— transmits pilot and data channels
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IS-856 Reverse Link
• IS-856 only operations— transmits MAC and
ACK channels— MAC information— reverse rate indicator
(RRI)— data rate control
(DRC)
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IS-856 Reverse Link
Reverse channel structureIn the reverse direction, the access
terminal can use access or traffic channel— access and traffic
channels are code multiplexed
Access channel mode:— access terminal is idle and
transmits pilot and data channels
Traffic channel:— access terminal
is connected and transmits MAC, data, pilot and ACK channels
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IS-856 Reverse Link
Reverse channel usage
• Once connected, the access terminal is either in idle or connected state
• idle: monitors forward control channel
• connected: monitors forward traffic and control channels
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IS-856 Reverse Link
Access channel• consisting of a pilot and data channel• used by the access terminal to initiate
communication with the access network• respond to an access terminal directed
message• access terminal sends a series of access
probes (preamble followed by one or more access channel physical layer packets) until it receives a response from the access network access probe consists of a preamble followed by one or more access channel
• During preamble only pilot channel is transmitted
• During the access channel physical layer packet transmission, both the pilot channel and the data channel are transmitted
• physical layer packets transmitted at fixed data rate of 9.6 Kbps
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IS-856 Reverse Link
Reverse traffic channel
• comprised of pilot, MAC, ACK and data channels
• On the pilot channel, reverse rate indicator bits are time-multiplexed with the pilot bits
• ACK channel protected with repetition followed by spreading with 8-bit Walsh code W4
• data rate control (DRC) bits encoded and repeated for proper data protection.
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IS-856 Reverse Link
• Reverse rate indicatorThe reverse rate indicator (RRI)
channel is used by the access terminal to indicate the data rate at which the data channel is transmitted.
• Reverse ACK channelIn the CDMA2000 1xEV-DO
system, acknowledgment is provided at the physical layer. This provides quick response from the receiver (access terminal) to the transmitter (access network).
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IS-856 Reverse Link
Data rate control (DRC)• DRC channel in the reverse traffic
channel is used to indicate the selected serving sector and the requested data rate on the forward traffic channel
Reverse link parameters• access terminal selects a data rate
and sends the data traffic at the selected rate on the reverse traffic channel and it also sends reverse rate indicator (RRI) in time division multiplexed fashion with the pilot channel
Reverse link power control• the power control command is
repeated four times and sent in the MAC channel
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IS-856 Reverse Link
Medium access control (MAC) layer
• responsible for determining scheduling and transmission policies
• MAC layer determines the best possible data rate on slot-by-slot basis in both directions
• physical layer is responsible for actual transmission procedures based on input from MAC layer
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IS-856 Medium access control
Medium access control (MAC) functions
• Forward direction— Scheduling transmission
for different access terminals based on input given by these terminals
— handles scheduling transmission for forward control channel and forward traffic channel
— responsible for providing input to access terminals on the reverse link so that the access terminal can adjust reverse link data rates.
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IS-856 Medium access control
Medium access control (MAC) functions
• Reverse direction— handles transmission and
reception on access and traffic channel
— provides input to the access network on what is the best data rate and best sector based on the existing channel conditions.
— responsible for best possible data for transmission on the reverse link
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IS-856 Media access control
Media access control (MAC) protocols
Each protocol defines procedures and messages for handling of one and only one channel.
• access channel protocol
• control channel MAC protocol
• forward traffic channel MAC protocol
• reverse traffic channel MAC protocol
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IS-856 Media access control
Media access control (MAC) states• The FTC-MAC can be in one of the
three states when the access terminal is activated. The various states are described briefly here:— inactive state: when the access
terminal is not assigned a forward traffic channel (not connected)
— variable rate state: when access terminal is assigned a forward traffic channel (connected)
— fixed rate state: the access terminal always receives traffic from one particular sector in its active set at a fixed rate
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Lesson 5:
Theory of operations
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Theory of operations
Evolving to CDMA2000 1xEV-DO
• Goals of CDMA2000 1xEV-DO— provide efficient packet-based air interface— Sharing components with CDMA 1X— Reduced cost of ownership
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Theory of operations
Evolving to CDMA2000 1xEV-DO (continued)
• IP network accessCDMA2000 1xEV-DO and CDMA2000 1X systems share the
same packet data network infrastructure
• Packet data model—mobile switching center (MSC/MTX) and home location
registry (HLR) no longer required—MSC/MTX, HLR are responsible for radio access
authentication and authorization functions not data functions —packet data service authentication comes from a AAA (or
AN-AAA) server
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Theory of operations
Evolving to CDMA2000 1xEV-DO
• Packet data calls in CDMA2000 1xEV-DOThe CDMA2000
1xEV-DO networks support the same two IP addressing options for packet data as CDMA2000 1X networks:
— simple IP— mobile IP
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Theory of operations
Handoffs
• IS-856 does not support soft handoffs in the forward link
• IS-95/2000 supports soft handoffs in the forward link
• IS-856 supports soft handoff In the reverse link similar toIS-95 and IS-2000
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Theory of operations
Time-division multiplexing
• TDM used in forward direction
• Each user given dedicated time slot on entire 1.25 MHz carrier for their period of time
• TDM removes inefficiencies (overhead) of power control and soft handoff
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Theory of operationsFixed power variable rateThe CDMA2000 1xEV-DO system
based on fixed power variable rate
• sector transmits at full power to every access terminal
• data rate varies depending on the interference experienced by the access terminal
• access terminal reports receivable data rates based on interference conditions for every scheduling period
• network transmits to the access terminal at that rate during that period
• The time slot and data rate for each connected user is adaptively determined by the scheduler so as to enhance CDMA2000 1xEV-DO aggregate forward data throughput
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Appendix A:
Call processing
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1X EV-DO Basic Call Processing
This section will cover different call processing scenarios including:
• Registration
• Call Flow
• Handoffs—DOM to DOM—DOM to 1X—1X to 1xEV-DO
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Access Terminal Registration
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Access terminal call origination
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PDSN call origination
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Handoff DOM to DOM
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Handoff DOM to 1X system
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Handoff 1X to 1X EV-DO System
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