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RAN BOOTP and DHCP Description Issue 01 Date 2009-03-30 Huawei Technologies Co., Ltd. provides customers with comprehensive technical Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd

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RAN

BOOTP and DHCP Description

Issue 01

Date 2009-03-30

Huawei Technologies Co., Ltd. provides customers with comprehensive technical support and service. For

Huawei Proprietary and Confidential Copyright © Huawei Technologies Co.,

Ltd

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any assistance, please contact our local office or company headquarters.

Huawei Technologies Co., Ltd.Address: Huawei Industrial Base

Bantian, LonggangShenzhen 518129People's Republic of China

Website: http://www.huawei.com

Email: [email protected]

Copyright © Huawei Technologies Co., Ltd. 2009. All rights reserved.No part of this document may be reproduced or transmitted in any form or by any means without prior written consent of Huawei Technologies Co., Ltd.

Trademarks and Permissions

and other Huawei trademarks are trademarks of Huawei Technologies Co., Ltd.All other trademarks and trade names mentioned in this document are the property of their respective holders.

NoticeThe information in this document is subject to change without notice. Every effort has been made in the preparation of this document to ensure accuracy of the contents, but all statements, information, and recommendations in this document do not constitute the warranty of any kind, express or implied.

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About This Document

About This Document

AuthorPrepared by

Zhang Ling Date 2009-03-04

Edited by Meng Yuan Date 2009-03-11

Reviewed by

Li Liang, Cheng Xiaoli, Sun Jingshu, Zhang Jianhua, Xin Lichen

Date 2009-03-09

Translated by

Tong Aruna Date 2009-03-16

Tested by Gao Bingxin Date 2009-03-15

Approved by

Li Qiang Date 2009-03-30

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RANBOOTP and DHCP Description

Contents

Contents

1 Change History...........................................................................1-32 Introduction...............................................................................2-33 BOOTP Description......................................................................3-3

3.1 BOOTP Overview..........................................................................................................................................3-33.2 BOOTP Principle............................................................................................................................................3-3

3.2.1 Port Listening........................................................................................................................................3-33.2.2 Port Configuration.................................................................................................................................3-33.2.3 PVC Setup and BOOTP Request Initiation...........................................................................................3-33.2.4 BOOTREPLY Message Returned by the RNC.....................................................................................3-33.2.5 IPoA Configuration...............................................................................................................................3-3

3.3 Configuring BOOTP......................................................................................................................................3-33.3.1 Configuring BOOTP on the RNC Side.................................................................................................3-33.3.2 Configuring BOOTP on the NodeB Side..............................................................................................3-3

4 DHCP Description........................................................................4-34.1 DHCP Overview.............................................................................................................................................4-34.2 DHCP Principle..............................................................................................................................................4-3

4.2.1 DHCP Message.....................................................................................................................................4-34.2.2 Port Configuration.................................................................................................................................4-34.2.3 DHCP Message Exchange.....................................................................................................................4-3

4.3 DHCP Relay Principle....................................................................................................................................4-34.4 DHCP in VLAN Networking.........................................................................................................................4-34.5 Configuring DHCP.........................................................................................................................................4-3

4.5.1 Configuring DHCP on the RNC Side....................................................................................................4-34.5.2 Configuring DHCP on the NodeB Side................................................................................................4-3

5 BOOTP and DHCP Parameters......................................................5-35.1 Description.....................................................................................................................................................5-35.2 Values and Ranges..........................................................................................................................................5-3

6 Reference Documents.................................................................6-3

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RANBOOTP and DHCP Description

1 Change History

1 Change History

The change history provides information on the changes in different document versions.

Document and Product VersionsDocument Version RAN Version

01 (2009-03-30) 11.0

This document is based on the BSC6810 and 3900 series NodeBs.

The available time of each feature is subject to the RAN product roadmap

There are two types of changes, which are defined as follows:

Feature change: refers to the change in the BOOTP and DHCP. Editorial change: refers to the change in the information that was inappropriately

described or the addition of the information that was not described in the earlier version.

01 (2009-03-30)This is the document for the first commercial release of RAN11.0.

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2 Introduction

2 Introduction

The BOOTstrap Protocol (BOOTP) and the Dynamic Host Configuration Protocol (DHCP) features are introduced to help telecom operators in saving time and effort for on-site maintenance and thus reducing the expenditure on operation and maintenance (OM). In the networking of the Radio Access Network (RAN) equipment, BOOTP is applicable to ATM networking whereas DHCP is applicable to IP networking.

The core concept of BOOTP and DHCP is that the NodeB can automatically obtain the IP address from the server when the configuration file is absent or incorrect in the NodeB (the initial configuration file might be incorrect, or after network reconfiguration the original configuration file cannot adapt to the current networking mode). In this situation, the OM personnel remotely maintain the NodeB from the operation and maintenance center (OMC) by downloading again or modifying the configuration file.

BOOTPBOOTP applies to the ATM networking, whose core technology is IP over ATM (IPoA).In ATM networking, if the network layer protocol used by the NodeB is the IP protocol, that is, the NodeB corresponds to an IP address, the IP protocol must be combined with the ATM protocol to use the LMT or M2000 to maintain the NodeB. This constitutes the IPoA technology.BOOTP helps the NodeB to establish an IPoA path and this facilitates to remotely maintain the NodeB when the configuration file is absent or incorrect in the NodeB.

DHCPDHCP applies to the IP networking, whose core technology is that through special message exchange, the NodeB obtains the IP address from the server. When the RNC or M2000 acts as the DHCP server, the RNC or M2000 assigns IP addresses to NodeBs.When the DHCP feature supported by the Huawei NodeB contains the DHCP Relay function, the NodeB supports DHCP on the cascading network. In addition, the DHCP feature of the Huawei NodeB also applies to the Virtual Local Area Network (VLAN) networking.

Intended AudienceThis document is intended for:

System operators who need a general understanding of BOOTP and DHCP. Personnel working on Huawei products or systems.

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Impact Impact on system performance

None. Impact on other features

None.

Network Elements InvolvedTable 2-1 lists the network elements (NEs) involved in BOOTP and DHCP.

Table 2-1 NEs involved in BOOTP and DHCP

UE

NodeB

RNC

MSC Server MGW SGSN GGSN HLR

- √ √ - - - - -

NOTE -: not involved √: involved

UE = User Equipment, RNC = Radio Network Controller, MSC Server = Mobile Service Switching Center Server, MGW = Media Gateway, SGSN = Serving GPRS Support Node, GGSN = Gateway GPRS Support Node, HLR = Home Location Register

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3 BOOTP Description

3.1 BOOTP OverviewThe BOOTstrap Protocol (BOOTP) is used for the bootstrap of a diskless workstation. During the startup of the diskless workstation, the IP address can be obtained from the server. Compared with the Reverse Address Resolution Protocol (RARP) that implements the same function, BOOTP is more versatile and easy to use. BOOTP complies with the RFC 951 and RFC 1542 protocols.

To combine BOOTP with the RAN system, the NodeB should obtain the IP address and default PVC to establish an IPoA path; thus, an OM channel can be set up between the RNC and the NodeB.

Generally, the NodeB configuration file contains the configuration data of IPoA paths. If the data is correct, the user can remotely access and maintain the NodeB; if the data is incorrect, BOOTP helps the NodeB to establish a correct IPoA path and this facilitates to remotely maintain the NodeB.

3.2 BOOTP PrincipleBOOTP is used to set up a remote maintenance channel from the M2000 or LMT to the NodeB. In ATM networking, an IPoA path is required.

The configuration information required for setting up an IPoA path includes the Permanent Virtual Channel (PVC), transport ports carrying the PVC, and IP address.

In ATM networking, the following port types are preferred: Inverse Multiplexing over ATM (IMA), User Network Interface (UNI), fractional ATM, and unchannelized STM-1/OC-3. The BOOTP implementation process varies according to the port types.

Therefore, correct configuration is a prerequisite for implementing BOOTP. Figure 3-1 shows the process of implementing BOOTP.

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Figure 3-1 Process of implementing BOOTP

3.2.1 Port ListeningThe purpose of port listening is to listen to the configuration information of peer ports and thus to correctly configure the transport ports that carry PVCs in the NodeB.

IMA/UNIThrough IMA/UNI ports (the types of physical interfaces can be E1, T1, or channelized STM-1/OC-3), the NodeB can obtain the configuration information from peer ports by listening to the IMA Control Protocol (ICP) cells of the peer end. Then, the NodeB correctly sets up an

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IMA group that carries the PVC (including the IMA links in the IMA group) or UNI links according to the configuration information.

Fractional ATMThe fractional ATM link requires a bitmap of all types of timeslots contained in the link. If the timeslots are inconsistent between the two ends, the setup of a fractional ATM link fails.

Using a brute attack method to listen to the timeslots is time consuming as the combinations of timeslots are infinite, and therefore the BOOTP technology may lose its advantage.

To prevent attempting a large number of timeslot combinations, you need to minimize the range of combinations, which contains only the timeslot bitmaps used by the telecom operators. Thus, the NodeB makes attempts only within these timeslot bitmaps.

For E1 links (each link contains thirty-two 64 kbit timeslots), the NodeB uses the following timeslot bitmaps:

{0xFFFE,0x2FFFE,0x7FFE,0x6FFFE,0x3FFE,0xEFFFE,0x1FFE,0x1EFFFE,0xFFE,0x3EFFFE,0x7FE, 0x7EFFFE, 0x3FE, 0xFEFFFE, 0x1FEFFFE, 0x3FEFFFE, 0x7FEFFFE, 0xFFEFFFE, 0x1FFEFFFE,0x3FFEFFFE, 0x7FFEFFFE, 0xFFFEFFFE, 0x1FE, 0xFE, 0x7E, 0x3E, 0x1E, 0xE, 0x6, 0x2}

For T1 links (each link contains twenty-four 64 kbit timeslots), the NodeB uses the following timeslot bitmaps:

{0x7FFF,0xFFFF,0x3FFF,0x1FFFF,0x1FFF,0x3FFFF,0xFFF,0x7FFFF,0x7FF,0xFFFFF,0x3FF, 0x1FFFFF, 0x1FF,0x3FFFFF,0x7FFFFF, xFFFFFF,0xFF,0x7F,0x3F,0x1F,0xF,0x7,0x3,0x1}

To listen to fractional ATM links is to apply the brute attack method to these timeslot bitmaps, which is a way to configure the fractional ATM links. If the links are normal, the listening succeeds; if the links are abnormal, the timeslot bitmaps may not match the configuration of the peer end, and you need to try other timeslot bitmaps.

After the listening succeeds, you can set up a PVC without configuring the ports.

Unchannelized STM-1/OC-3The unchannelized STM-1/OC-3 links can directly set up PVCs without listening to any ports because interconnection problems are not involved.

RestrictionsPort listening has the following restrictions:

A prerequisite for BOOTP is that physical links must be connected normally. If a link is abnormal, ports are not configured on this link.

The transport ports on the transmission equipment working between the RNC and the NodeB must be correctly configured.

The NodeB first listens to the IMA/UNI ports because initially it is difficult to determine whether to use the IMA/UNI ports or fractional ATM ports. If the listening fails, the NodeB listens to the fractional ATM ports.

The NodeB first uses the E1 timeslot bitmaps to listen to the ports, because initially it is difficult to determine whether the physical links connected to the NodeB are E1s or T1s. If the listening fails, the NodeB uses the T1 timeslot bitmaps for listening. To listen to the IMA/UNI and fractional ATM ports, the sequence of "E1 prior to T1" is preferred.

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3.2.2 Port ConfigurationFor the configuration of IMA and UNI ports, after the NodeB listens to the configuration information of peer ports, it configures the NodeB ports by selecting the common configuration parameters, such as IMA protocol version number and IMA frame length, according to the configuration information.

3.2.3 PVC Setup and BOOTP Request InitiationThe PVC used by BOOTP is fixed to 1/33, that is, its Virtual Path Identifier (VPI) is set to 1 and Virtual Channel Identifier (VCI) is set to 33. On the RNC or ATM network equipment side, the PVC fixed to 1/33 must be configured. The BOOTP process is implemented on this PVC.

After the PVC is set up, the NodeB initiates a BOOTP request on this PVC, that is, the NodeB requests the RNC to assign an IP address and uses it as a maintenance address. Users can visit this address to log in to and maintain the NodeB.

3.2.4 BOOTREPLY Message Returned by the RNCThe prerequisite for the RNC to send a BOOTREPLY message is that the RNC configures the PVCs fixed to 1/33 and has corresponding IP addresses.

On these PVCs, the RNC receives a BOOTREQUEST message from the NodeB and returns a BOOTREPLY message to the NodeB. The BOOTREPLY message contains the IP address assigned to the NodeB.

3.2.5 IPoA ConfigurationAfter the NodeB receives the BOOTREPLY message from the RNC, the NodeB begins to configure an IPoA path, which is the end of the BOOTP implementation process.

3.3 Configuring BOOTP3.3.1 Configuring BOOTP on the RNC Side

On the RNC side, you can use the ADD IPOAPVC command to configure the PVC. When using BOOTP, you need to configure the PVC as VPI = 1 and VCI = 33. The key parameters of this command are as follows:

CARRYVPI: set to 1. CARRYVCI: set to 33. IPADDR: local IP address. PEERIPADDR: IP address of the peer end, that is, IP address of the NodeB.

On the RNC side, you can use the ADD NODEBIP command to configure the IP address of the maintenance channel. The key parameter of this command is as follows:

NBATMOAMIP: OM address of the NodeB ATM transmission.

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3.3.2 Configuring BOOTP on the NodeB SideThe BOOTP process can be implemented without NodeB configuration files, and therefore it is unnecessary to configure BOOTP on the NodeB side.

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4 DHCP Description

4.1 DHCP OverviewThe Dynamic Host Configuration Protocol (DHCP) is based on BOOTP. The DHCP feature provides configuration information for the Internet host in the TCP/IP network.

DHCP is built on the client/server model. Using DHCP, the client requests parameters such as IP address, subnet mask, and default gateway from the server. After receiving the request, the server sends the configuration information to the client. DHCP complies with the RFC 2131 and RFC 2132 protocols.

In the RAN system, the NodeB acts as the DHCP client, and the RNC or M2000 acts as the DHCP server to assign an IP address to the NodeB. As defined in the DHCP protocol, when the Iub interface uses IP transport, the NodeB automatically obtains the IP address and other configuration information after startup, and thus an OM channel is automatically set up between the NodeB and the RNC or M2000.

The DHCPREQUEST message is broadcast but cannot traverse the layer 3 network. Therefore, to implement the DHCP process in the NodeB on the IP cascading network, the NodeB also supports the DHCP Relay function. DHCP Relay also complies with the RFC 2131 and RFC 2132 protocols.

Besides, in VLAN networking, if initially the NodeB does not have any configuration files, it is difficult to determine whether the DHCP messages need to enable the VLAN, or how to enable the VLAN, or which type of VLAN is to be enabled. Therefore, DHCP in VLAN networking requires its own solution.

4.2 DHCP Principle4.2.1 DHCP Message

All types of DHCP messages are encapsulated in the User Datagram Protocol (UDP) datagrams, as shown Figure 4-1. The DHCP server uses UDP port 67, and the DHCP client uses UDP port 68.

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Figure 4-1 Encapsulation of DHCP messages

4.2.2 Port ConfigurationIn IP networking, the NodeB supports the following types of ports:

FE ports: There is no need to configure FE ports as the DHCP messages can be sent directly.

MLPPP/PPP ports: There is a need to configure MLPPP/PPP ports on the RNC side so that the DHCP messages can be sent.

The MLPPP/PPP links in IP networking also require timeslot bitmaps. If the timeslot bitmaps are inconsistent between the two ends, the communication fails.

Similarly, using the brute attack method to listen to the timeslots of MLPPP/PPP links is time consuming as the combinations of timeslots are infinite, and therefore the DHCP technology may lose its advantage.

To prevent attempting a large number of timeslot combinations, you need to minimize the range of combinations, which contains only the timeslot bitmaps used by the telecom operators. Thus, the NodeB makes attempts only within these timeslot bitmaps.

For E1 links (each link contains thirty-two 64 kbit timeslots), the NodeB uses the following timeslot bitmaps:

{0xFFFE,0x2FFFE,0x7FFE,0x6FFFE,0x3FFE,0xEFFFE,0x1FFE,0x1EFFFE,0xFFE,0x3EFFFE,0x7FE, 0x7EFFFE, 0x3FE, 0xFEFFFE, 0x1FEFFFE, 0x3FEFFFE, 0x7FEFFFE, 0xFFEFFFE, 0x1FFEFFFE,0x3FFEFFFE, 0x7FFEFFFE, 0xFFFEFFFE, 0x1FE, 0xFE, 0x7E, 0x3E, 0x1E, 0xE, 0x6, 0x2}

For T1 links (each link contains twenty-four 64 kbit timeslots), the NodeB uses the following timeslot bitmaps:

{0x7FFF,0xFFFF,0x3FFF,0x1FFFF,0x1FFF,0x3FFFF,0xFFF,0x7FFFF,0x7FF,0xFFFFF,0x3FF, 0x1FFFFF, 0x1FF,0x3FFFFF,0x7FFFFF, xFFFFFF,0xFF,0x7F,0x3F,0x1F,0xF,0x7,0x3,0x1}

Using one of the bitmaps, the NodeB negotiates with the peer end. If the negotiation succeeds, it is considered that the timeslot bitmap can ensure the communication with the peer end. After the negotiation, the NodeB enters the DHCP implementation process. If the negotiation fails, it is considered that the timeslot bitmap does not match the peer end configuration, and the NodeB needs to try other timeslot bitmaps.

Similar to fractional ATM links, the MLPPP/PPP links have the following restrictions:

A prerequisite for DHCP is that physical links must be connected normally. If a link is abnormal, ports are not configured on this link.

The transport ports on the transmission equipment working between the RNC and the NodeB must be correctly configured.

The NodeB first uses FE ports to initiate the DHCP implementation process because initially it is difficult to determine whether to use the FE ports or MLPPP/PPP ports. If the initiation fails, the NodeB uses the MLPPP/PPP ports.

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The NodeB first uses the E1 timeslot bitmaps to listen to the MLPPP/PPP links, because initially it is difficult to determine whether the physical links connected to the NodeB are E1s or T1s. If the listening fails, the NodeB uses the T1 timeslot bitmaps to listen to the MLPPP/PPP links.

4.2.3 DHCP Message ExchangeThe process of DHCP message exchange has four steps and involves the following messages: DHCPDISCOVER, DHCPOFFER, DHCPREQUEST, and DHCPACK. Figure 4-1 shows the process of DHCP message exchange.

Figure 4-1 Process of DHCP message exchange

Step 1 The DHCP client broadcasts a DHCPDISCOVER message.

The DHCP client initiates the DHCPDISCOVER message and broadcasts it to the network. The DHCP client attempts to find the DHCP server and waits for a response from the DHCP server. The DHCP server will assign an IP address to the DHCP client as a response to the DHCPDISCOVER message.

In the RAN system, after startup the NodeB sends a DHCPDISCOVER message to the network and waits for a response from the DHCP server if the NodeB does not have any configuration file or its configuration file is incorrect.

Step 2 The DHCP server returns a DHCPOFFER message.

After the DHCP server (in the RAN system, the DHCP server can be the RNC or M2000) receives the DHCPDISCOVER message, it sends a DHCPOFFER message to the DHCP client. The DHCPOFFER message contains the IP address assigned to the client and the related configuration information.

Step 3 The DHCP client selects a server and sends a DHCPREQUEST message to the server.

Multiple DHCP servers may exist in the network and the DHCPDISCOVER message is broadcast on the network. Therefore, the DHCP client sending the DHCPDISCOVER message may receive DHCPOFFER messages from multiple servers. The DHCP client selects the DHCPOFFER message of a server as its configuration information (the NodeB uses the first received DHCPOFFER message as a reference for its configuration), and then broadcasts the DHCPREQUEST message to the network, notifying all the DHCP servers of the information about the selected DHCP server.

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Step 4 The selected DHCP server responds with a DHCPACK message.

The DHCP server acts as the selected server of the client. After receiving the DHCPREQUEST message, the selected DHCP server sends the DHCPACK message to the client to confirm that the process of assigning an IP address ends. Then, the DHCP message exchange is complete.

The DHCPDISCOVER and DHCPREQUEST messages are broadcast by the client so that all the DHCP servers can receive the messages. This ensures that the client is assigned an IP address or other exceptions are prevented from taking place.

----End

4.3 DHCP Relay PrincipleThe DHCPDISCOVER messages are broadcast messages but they cannot traverse routers. Obviously, configuring a DHCP server on each subnet to assign an IP address is not economical. For the client to obtain an IP address from the DHCP server on other physical subnets, the DHCP Relay technology is required.

In the RAN system, it is unnecessary for the NodeB to use DHCP Relay on a non-cascading network. As broadcast messages cannot traverse a hub NodeB in IP cascading networking (the hub NodeB works as a router in the layer 3 network and so broadcast messages cannot traverse a hub NodeB), DHCP Relay is required for a hub NodeB. With DHCP Relay applied, broadcast messages can be converted into unicast messages before being forwarded. In this sense, DHCP Relay provides a transparent transmission mechanism for DHCP broadcast messages.

The prerequisite for using DHCP Relay is that the hub NodeB has correct configuration files and is working in normal state instead of DHCP state. Also, the hub NodeB is configured with the DHCP Relay function.

For better understanding of DHCP Relay, the following figures compare two different processes:

Process of the first application for an IP address when DHCP Relay is used Process of the first application for an IP address when DHCP Relay is not used

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Figure 4-1 Process of the first application for an IP address when DHCP Relay is used

Figure 4-2 Process of the first application for an IP address when DHCP Relay is not used

When DHCP Relay is used on the NodeB side, a DHCP server address should be configured in the hub NodeB. Thus, when the hub NodeB receives a DHCPDISCOVER message from the lower-level node, it will change the giaddr field in the message to the IP address of the port that receives the DHCPDISCOVER message (For the definition and description of giaddr, see the RFC 2131 protocol). Then, it forwards the DHCPDISCOVER message to the DHCP server.

After receiving the DHCPDISCOVER message from the hub NodeB, the DHCP server first checks the giaddr field in the message.

If giaddr is 0 (which means that DHCP Relay is not used), the DHCP server considers that the client is on the same subnet as itself. Then, the DHCP server assigns an IP address from the address pool to the client according to the network segment that its own IP address belongs to.

If giaddr is not 0 (which means that the received DHCPDISCOVER message is forwarded through DHCP Relay), the DHCP server assigns an IP address from the address pool to the client according to the network segment that the IP address filled in the giaddr field belongs to.

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4.4 DHCP in VLAN NetworkingIn VLAN networking, the telecom operators can benefit from the following aspects:

The VLAN cos tag (representing the VLAN priority) implements differentiated services of the layer 2 network.

Different VLAN IDs can isolate traffic so as to improve network security. For example, they can isolate network maintenance data traffic from voice data traffic, or isolate real-time data traffic from non-real-time data traffic.

Different VLANs can limit traffic. For example, the VLAN traffic configured for HSPA services is 10 Mbit/s, whereas the VLAN traffic configured for R99 services is 2 Mbit/s.

Figure 4-1 shows typical VLAN networking.

Figure 4-1 Typical VLAN networking

In VLAN networking, a NodeB uses a single VLAN; multiple NodeBs share one VLAN, but a NodeB cannot use multiple VLANs.

If DHCP is applied when the NodeB has no configuration files, the NodeB does not determine which VLAN tag to use before sending a DHCPDISCOVER message. If the VLAN tag is not determined, the NodeB cannot send the message to the DHCP server.

Therefore, in VLAN networking, the key problem is how the NodeB determines which VLAN tag to use. To solve this problem, VLAN detection is required.

The purpose of VLAN detection is to familiarize the NodeB with the VLAN used by the current network. VLAN detection serves as a reference for the following DHCP negotiation and prevents the NodeB from broadcasting messages to all VLANs.

The VLAN tag used in the message sent by the NodeB is determined by checking the types of VLANs contained in the message received by the NodeB.

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The NodeB records the VLAN tags in the messages in sequence when sending the messages. If the DHCP server expires when the NodeB records a VLAN tag, the NodeB will try the next VLAN tag until the DHCP server receives the message.

Combined with VLAN detection, DHCP is applicable to VLAN networking.

4.5 Configuring DHCP4.5.1 Configuring DHCP on the RNC Side

On the RNC side, you can use the ADD NODEBESN command to add an Electronic Serial Number (ESN) of the NodeB in response to the DHCP request made by the NodeB. The key parameters of this command are as follows:

NBLB1: specifies ESN 1 of the NodeB. If the NodeB is configured with two main processing boards, two ESNs are required; if the NodeB is configured with one main processing board, only one ESN is required.

NBLB2: specifies ESN 2 of the NodeB. This parameter is required only when the NodeB is configured with two main processing boards.

On the RNC side, you can use the ADD NODEBIP command to configure the maintenance address of the NodeB. The key parameter of this command is as follows:

NBIPOAMIP: specifies the maintenance address of the NodeB in IP transmission.

4.5.2 Configuring DHCP on the NodeB SideThe DHCP process can be implemented without NodeB configuration files, and therefore it is unnecessary to configure DHCP on the NodeB side.

If required, DHCP Relay is configured in the hub NodeB.

On the NodeB side, you can use the ADD DHCPSVRIP command to configure DHCP Relay. The key parameter of this command is as follows:

DHCPSVRIP: specifies the IP address of the DHCP server. After the IP address is configured, the hub NodeB enables DHCP Relay to send the DHCP message of the client to this IP address. One NodeB can be configured with only one IP address of the DHCP server, and the IP address is valid for all the ports on the NodeB.

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5 BOOTP and DHCP Parameters

5.1 DescriptionTable 5-1 BOOTP and DHCP parameter description

Parameter ID Description

CARRYVPI The value of bearing VCI.VCI of the SAAL link that goes out of the RNC.

CARRYVCI The value of bearing VPI.VPI of the SAAL link that goes out of the RNC.

IPADDR DHCP Server IP Address

PEERIPADDR This IP address is the local IP address of the Ethernet port.

NBATMOAMIP NodeB ATM_TRANS IP address.

NBLB1 NodeB IP_TRANS IP address.

NBLB2 This parameter indicates the first electronic serial number.

NBIPOAMIP This parameter indicates the second electronic serial number.

DHCPSVRIP This parameter indicates the peer IP address.

5.2 Values and RangesTable 5-1 BOOTP and DHCP parameter values and parameter ranges

Parameter ID

Default Value

GUI Value Range

Actual Value Range

Unit MML Command NE

CARRYVCI - 32~65535 32~65535 None ADD IPOAPVC(Optional) RNC

CARRYVPI - 0~255 0~255 None ADD IPOAPVC(Optional) RNC

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Parameter ID

Default Value

GUI Value Range

Actual Value Range

Unit MML Command NE

DHCPSVRIP - - 0.0.0.0~255.255.255.255 None

ADD DHCPSVRIP(Mandatory)

NodeB

IPADDR - - 0.0.0.0~255.255.255.255 None ADD

IPOAPVC(Mandatory) RNC

NBATMOAMIP - - 0.0.0.0~255.255.255.255 None ADD

NODEBIP(Mandatory) RNC

NBIPOAMIP - - 0.0.0.0~255.255.255.255 None ADD

NODEBIP(Mandatory) RNC

NBLB1 - - 1 to 30 characters None

ADD NODEBESN(Mandatory)

RNC

NBLB2 - - 1 to 30 characters None

ADD NODEBESN(Mandatory)

RNC

PEERIPADDR - - 0.0.0.0~255.255.255.255 None ADD

IPOAPVC(Mandatory) RNC

The Default Value column is valid for only the optional parameters.The "-" symbol indicates no default value.

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6 Reference Documents

The following lists the reference documents related to the feature:

1. RFC9512. RFC15423. RFC21314. RFC21325. Basic Feature Description of Huawei UMTS RAN11.0 V1.56. Optional Feature Description of Huawei UMTS RAN11.0 V1.5

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