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VPP_UPF_CONFIG_GENERATION.md

VPP UPF Configuration Generation

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VPP_UPF_CONFIG_GENERATION.md

init.conf

startup_debug.conf

upf_profile.json

create_configuration.py

The VPP-UPF configuration for different UPF deployment options (A-UPF, I-UPF, ULCL) are not compatible with each other.
The example described in VPP_UPF_CONFIG shows a central UPF node with one N3 and one N6
interface.

To ease the deployment, the UPF configuration can be auto-generated using the create_configuration.py script. It is
located in scripts/upf_conf/create_configuration.py. If you choose to use the official OAI docker images (from v1.5.0), this script is
executed upon start of the containers.

It takes three positional arguments:

usage: create_configuration.py[-h][--rename]init_pathprofile_pathstartup_path

The init_path is the path to the init file that will be generated. A json file is written to the profile_path which
contains the UPF profile which is sent to the NRF.

The startup_path requires an existing VPP startup_debug.conf file with placeholders (@value@). These will be
overwritten with the corresponding environment variables.

If you choose to rename using the --rename option, the host interfaces are renamed from e.g. eth1 to n6-3.
Which interface is renamed depends on the configured subnet.

Environment variables

The UPF configuration is built entirely from environment variables. There are static variables, which always have to be
present:

Environment Variable	Description	Used in
NAME	Used to build the UPF FQDN	init.conf, profile.json
MNC	Used to build the UPF FQDN	init.conf, profile.json
MCC	Used to build the UPF FQDN	init.conf, profile.json
REALM	Used to build the UPF FQDN	init.conf, profile.json
VPP_MAIN_CORE	Which CPU core ID to use for the main thread	startup_debug.conf
VPP_CORE_WORKER	Which CPU core ID to use for the worker thread *	startup_debug.conf
SNSSAI_SD	SD from the SNSSAI	profile.json
SNSSAI_SST	SST from the SNSSAI	profile.json
DNN	DNN	profile.json
VPP_PLUGIN_PATH	Path where the UPG VPP plugin is installed	startup_debug.conf

* This config from VPP allows to configure more than one worker thread, e.g. 1-4, but it is not recommended in the
VPP-UPF, as there are race conditions.

The UPF FQDN is built as follows:

<name>.node.5gcn.mnc<mnc>.mcc<mcc>.<realm>

The NAME variable is translated to lower-case.

Then, there are support features which you also have to configure:

Environment Variable	Description
REGISTER_NRF	If the UPF should register to NRF
NRF_IP_ADDR	The NRF IP address
NRF_PORT	The NRF Port
HTTP_VERSION	HTTP version towards NRF (1/2)

Apart from this global configuration, you can dynamically configure your interfaces.
The syntax to configure an interface is as follows:

IF_<Index>_<Value>

Each interface can have multiple values, whereas the index describes the interface.
The following values are available:

Value	Description	Mandatory
IP	IP address of the interface**	yes
TYPE	Either N3, N4, N6 or N9	yes
NWI	Network Instance of the interface	yes (not for N4)
DNAI	Data Network Access Identifier	no
IP_REMOTE	Next hop IP, optional when using --rename	yes/no

** Should belong to subnet of existing host interface

An example of a UPF configuration is as follows (see also the docker-compose file):

- IF_1_IP=192.168.70.201
- IF_1_TYPE=N4
- IF_2_IP=192.168.72.201
- IF_2_TYPE=N3
- IF_2_NWI=access.oai.org
- IF_3_IP=192.168.73.201
- IF_3_TYPE=N6
- IF_3_IP_REMOTE=192.168.73.135 # EXT-DN IP Address
- IF_3_NWI=internet.oai.org
- NAME=VPP-UPF
- MNC=95
- MCC=208
- REALM=3gppnetwork.org
- VPP_MAIN_CORE=0
- VPP_CORE_WORKER=1
- VPP_PLUGIN_PATH=/usr/lib/x86_64-linux-gnu/vpp_plugins/ # Ubntu18.04
- SNSSAI_SD=123
- SNSSAI_SST=222
- DNN=default
- REGISTER_NRF=yes
- NRF_IP_ADDR=192.168.70.130
- NRF_PORT=80
- HTTP_VERSION=1

Interfaces

We use veth pairs to configure the UPF interfaces. Each UPF interface (e.g. N3) has a host interface IP and the IP address
used for signaling. You need one subnet for each UPF interface. In a typical deployment, you need at least three subnets:

• Signaling (N4)
• Access (N3)
• Core/Internet (N6).

The IP value should belong to the same subnet as the host interface, but must not be the same.

The IP_REMOTE value also needs to be in the same subnet and is used to setup the routes accordingly.
When you use the --rename option, the IP_REMOTE is automatically calculated from the subnet from the IP value.
The remote IP is always the first host in the subnet, e.g. for the IP 192.168.70.201 in the subnet 192.168.70.0/24,
the remote IP is 192.168.70.1.

The value you provide overrides the default value. When you do not rename the interfaces, you need to manually specify
the remote IP address.

Interface Configuration Examples

The dynamic creation allows you to configure different UPF types.

Central UPF

This UPF has one N3, one N4 and one N6 interface:

- IF_1_IP=192.168.70.201
- IF_1_TYPE=N4
- IF_2_IP=192.168.72.201
- IF_2_TYPE=N3
- IF_2_NWI=access.oai.org
- IF_3_IP=192.168.73.201
- IF_3_TYPE=N6
- IF_3_NWI=internet.oai.org

A-UPF

This UPF has one N9, one N4 and one N6 interface:

- IF_1_IP=192.168.70.202
- IF_1_TYPE=N4
- IF_2_IP=192.168.74.202
- IF_2_TYPE=N9
- IF_2_NWI=iupf.node.5gcn.mnc98.mcc208.3gppnetwork.org
- IF_2_DNAI=iupf
- IF_3_IP=192.168.75.202
- IF_3_TYPE=N6
- IF_3_NWI=internet.oai.org
- IF_3_DNAI=internet

When you want to use multiple UPFs which should be chained or form a graph, you need to ensure that the NWI of the
configuration matches the FQDN of the other UPF. In this case, IUPF should have the following FQDN config:

- NAME=IUPF
- MNC=98
- MCC=208
- REALM=3gppnetwork.org

I-UPF

This UPF has one N3, one N4 and one N9 interface:

- IF_1_IP=192.168.70.203
- IF_1_TYPE=N4
- IF_2_IP=192.168.72.203
- IF_2_TYPE=N3
- IF_2_NWI=access.oai.org
- IF_2_DNAI=access
- IF_3_IP=192.168.74.203
- IF_3_TYPE=N9
- IF_3_NWI=aupf.node.5gcn.mnc98.mcc208.3gppnetwork.org
- IF_3_DNAI=aupf

As you can see, the N9 interface is in the same subnet as the N9 interface of the I-UPF example. This means
that the SMF will create an edge between these two nodes (as long as the FQDN/NWI configuration matches).
Also, the DNAI is configured for these examples to enable SMF in selecting a specific UPF for a PDU session.

UL CL

This UPF has one N3, one N4 and two N9 interfaces:

- IF_1_IP=192.168.70.204
- IF_1_TYPE=N4
- IF_2_IP=192.168.72.204
- IF_2_TYPE=N3
- IF_2_NWI=access.oai.org
- IF_2_DNAI=access
- IF_3_IP=192.168.74.204
- IF_3_TYPE=N9
- IF_3_NWI=aupf1.node.5gcn.mnc98.mcc208.3gppnetwork.org
- IF_3_DNAI=aupf1
- IF_4_IP=192.168.76.204
- IF_3_TYPE=N9
- IF_3_NWI=aupf2.node.5gcn.mnc98.mcc208.3gppnetwork.org
- IF_4_DNAI=aupf2

FEATURE_SET.md

FEATURE_SET.md

VPP_UPG_CLI

VPP-UPF 可以进行的一些操作

$ docker exec -it vpp-upf ./bin/vppctl show upf helpadf                            show upf adf commandsapplication                    show upf application <name>applications                   show upf applications [verbose]association                    show upf associationbihash                         show upf bihash <v4-tunnel-by-key | v6-tunnel-by-key | qer-by-id | peer-index-by-ip> [detail|verbose]flows                          show upf flowsflow                           show upf flow commandsgtpu                           show upf gtpu commandsnode-id                        show upf node-idnwi                            show upf nwipfcp                           show upf pfcp commandspolicy                         show upf policyproxy                          show upf proxysession                        show upf sessionspecification                  show upf specification commandstdf                            show upf tdf commands

• Show PFCP session at UPF

$ docker exec -it vpp-upf ./bin/vppctl show upf session
CP F-SEID: 0x0000000000000001 (1) @ 192.168.70.133
UP F-SEID: 0x0000000000000001 (1) @ 192.168.70.202PFCP Association: 0TEID assignment per choose ID
PDR: 1 @ 0x7f6cef01cd00Precedence: 0PDI:Fields: 0000000dSource Interface: AccessNetwork Instance: access.oai.orgLocal F-TEID: 218138074 (0x0d0085da)IPv4: 192.168.72.202UE IP address (source):IPv4 address: 12.1.1.2SDF Filter [1]:permit out ip from any to assigned Outer Header Removal: GTP-U/UDP/IPv4FAR Id: 1URR Ids: [1] @ 0x7f6ceefde850QER Ids: [] @ 0x0
PDR: 2 @ 0x7f6cef01cd80Precedence: 0PDI:Fields: 0000000cSource Interface: CoreNetwork Instance: core.oai.orgUE IP address (destination):IPv4 address: 12.1.1.2SDF Filter [1]:permit out ip from any to assigned Outer Header Removal: noFAR Id: 2URR Ids: [1] @ 0x7f6ceefde8e0QER Ids: [] @ 0x0
FAR: 1Apply Action: 00000002 == [FORWARD]Forward:Network Instance: core.oai.orgDestination Interface: 1
FAR: 2Apply Action: 00000002 == [FORWARD]Forward:Network Instance: access.oai.orgDestination Interface: 0Outer Header Creation: [GTP-U/UDP/IPv4],TEID:9acb0442,IP:192.168.72.141
URR: 1Measurement Method: 0002 == [VOLUME]Reporting Triggers: 0001 == [PERIODIC REPORTING]Status: 0 == []Start Time: 2022/09/02 07:29:30:476vTime of First Usage:       0.0000 vTime of Last Usage:        0.0000 VolumeUp:    Measured:                    0, Theshold:                    0, Pkts:          0Consumed:                    0, Quota:                       0Down:  Measured:                    0, Theshold:                    0, Pkts:          0Consumed:                    0, Quota:                       0Total: Measured:                    0, Theshold:                    0, Pkts:          0Consumed:                    0, Quota:                       0Measurement Period:                   10 secs @ 2022/09/02 07:29:40:476, in     5.597 secs, handle 0x00000c01

参考文献

参考文献1：OAI 基础核心网部署：oai-cn5g-fed/docs/DEPLOY_SA5G_BASIC_DEPLOYMENT.md

参考文献2：oai-cn5g-upf-vpp

参考文献3：UPD_DEPLOY_HELP

参考文献4：vpp-upf-docs