Network Working Group L. Dunbar
Internet Draft H. Chen
Intended status: Standard Futurewei
Expires: April 26, 2021
October 26, 2020
OSPF extension for 5G Edge Computing Service
draft-dunbar-lsr-5g-edge-compute-ospf-ext-00
Abstract
This draft describes an OSPF extension that can dynamically
adjust network forwarding behavior based on Application
Servers' running status and environment. This feature can
greatly improve latency and performance for 5G Edge
Computing services.
The extension enables a feature, called soft anchoring,
which makes one Application Server at a specific location
to be more preferred than others for the same application
to receive packets from a specific source (UE).
Status of this Memo
This Internet-Draft is submitted in full conformance with
the provisions of BCP 78 and BCP 79.
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Internet-Drafts are working documents of the Internet
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Table of Contents
1. Introduction........................................... 3
1.1. 5G Edge Computing Background...................... 3
1.2. Problem#1: ANYCAST in 5G Edge Computing Environment
....................................................... 5
1.3. Problem #2: Unbalanced Anycast Distribution due to
UE Mobility............................................ 5
1.4. Problem 3: Application Server Relocation.......... 6
2. Conventions used in this document...................... 6
3. OSPF Extension for 5G EC............................... 8
3.1. Solution Overview................................. 8
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3.2. IP Layer Metrics to Gauge Application Behavior.... 9
3.3. To Equalize among Multiple ANYCAST Locations..... 10
3.4. OSPF Protocol Extension to advertise Load &
Capacity.............................................. 11
3.5. Reason for using IGP Based Solution:............. 11
3.6. OSPF Extension Using TE Stub Link................ 12
3.7. Aggregated Link Cost Solution.................... 15
4. Soft Anchoring of an ANYCAST Flow..................... 16
5. Manageability Considerations.......................... 17
6. Security Considerations............................... 17
7. IANA Considerations................................... 18
8. References............................................ 18
8.1. Normative References............................. 18
8.2. Informative References........................... 18
9. Acknowledgments....................................... 19
1. Introduction
This document describes an OSPF extension that can
dynamically adjust network forwarding behavior towards
Applications servers in 5G Edge Computing Environment based
on the Application Servers running status and the UE (User
Equipment) status.
1.1. 5G Edge Computing Background
As described in [5G-EC-Metrics], one Application can have
multiple Application Servers hosted in different Edge
Computing data centers that are close in proximity. Those
Edge Computing (mini) data centers are usually very close
to, or co-located with, 5G base stations, with the goal to
minimize latency and optimize the user experience.
When a UE (User Equipment) initiates application packets
using the destination address from a DNS reply or from its
own cache, the packets from the UE are carried in a PDU
session through 5G Core [5GC] to the 5G UPF-PSA (User Plan
Function - PDU Session Anchor). The UPF-PSA decapsulate the
5G GTP outer header and forwards the packets from the UEs
to the Ingress router of the Edge Computing (EC) Local Data
Network (LDN). The LDN for 5G EC, which is the IP Networks
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from 5GC perspective, is responsible for forwarding the
packets to the intended destinations.
When the UE moves out of coverage of its current gNB (next
generation Node B) (gNB1), handover procedures are
initiated and the 5G SMF (Session Management Function) also
selects a new UPF-PSA. The standard handover procedures
described in 3GPP TS 23.501 and TS 23.502 are followed.
When the handover process is complete, the UE has a new IP
address and the IP point of attachment is to the new UPF-
PSA. 5GC may maintain a path from the old UPF to new the
UPF for a short period of time for SSC [Session and Service
Continuity] mode 3 to make the handover process more
seamless.
+--+
|UE|---\+---------+ +------------------+
+--+ | 5G | +---------+ | S1: aa08::4450 |
+--+ | Site +--++---+ +----+ |
|UE|----| A |PSA| Ra| | R1 | S2: aa08::4460 |
+--+ | +---+---+ +----+ |
+---+ | | | | | S3: aa08::4470 |
|UE1|---/+---------+ | | +------------------+
+---+ |IP Network | L-DN1
|(3GPP N6) |
| | | +------------------+
| UE1 | | | S1: aa08::4450 |
| moves to | +----+ |
| Site B | | R3 | S2: aa08::4460 |
v | +----+ |
| | | S3: aa08::4470 |
| | +------------------+
| | L-DN3
+--+ | |
|UE|---\+---------+ | | +------------------+
+--+ | 5G | | | | S1: aa08::4450 |
+--+ | Site +--++-+--+ +----+ |
|UE|----| B |PSA| Rb | | R2 | S2: aa08::4460 |
+--+ | +--++----+ +----+ |
+--+ | | +-----------+ | S3: aa08::4470 |
|UE|---/+---------+ +------------------+
+--+ L-DN2
Figure 1: App Servers in different edge DCs
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1.2. Problem#1: ANYCAST in 5G EC Environment
Increasingly, Anycast is used extensively by various
application providers and CDNs because ANYCAST makes it
possible to dynamically load balance across server
instances based on network conditions.
Application Server location selection using Anycast address
leverages the proximity information present in the network
(routing) layer and eliminates the single point of failure
and bottleneck at the DNS resolvers and application layer
load balancers. Another benefit of using ANYCAST address is
removing the dependency on UEs. Some UEs (or clients) might
use their cached IP addresses instead of querying DNS for
extended period.
But, having multiple locations of the same ANYCAST address
in 5G Edge Computing environment can be problematic because
all those edge computing Data Centers can be close in
proximity. There might be very little difference in the
routing cost to reach the Application Servers in different
Edge DCs.
BGP is an integral part in the way IP Anycast usually
functions. Within BGP routing there are multiple routes for
the same IP address which are pointing to different
locations. But many Edge DCs could be within one IGP
domain, then there is no routing cost differentiation by
BGP. Same routing cost to multiple ANYCAST locations can
cause packets from one flow to be forwarded to different
locations, which can cause service glitches.
1.3. Problem #2: Unbalanced Anycast Distribution due to UE
Mobility
Another problem of using ANYCAST address for multiple
Application Servers of the same application in 5G
environment is that UEs' frequent moving from one 5G site
to another, which can make it difficult to plan where the
App Server should be hosted. When one App server is heavily
utilized, other App servers of the same address close-by
can be very underutilized. Since the condition can be short
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lived, it is difficult for the application controller to
anticipate the move and adjust.
1.4. Problem 3: Application Server Relocation
When an Application Server is added to, moved, or deleted
from a 5G Edge Computing Data Center, the routing protocol
has to propagate the changes to 5G PSA or the PSA adjacent
routers. After the change, the cost associated with the
site [5G-EC-Metrics] might change as well.
Note: for the ease of description, the Edge Application
Server and Application Server are used interchangeably
throughout this document.
2. Conventions used in this document
A-ER: Egress Router to an Application Server, [A-ER]
is used to describe the last router that the
Application Server is attached. For 5G EC
environment, the A-ER can be the gateway router
to a (mini) Edge Computing Data Center.
Application Server: An application server is a physical or
virtual server that host the software system
for the application.
Application Server Location: Represent a cluster of servers
at one location serving the same Application.
One application may have a Layer 7 Load
balancer, whose address(es) are reachable from
external IP network, in front of a set of
application servers. From IP network
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perspective, this whole group of servers are
considered as the Application server at the
location.
Edge Application Server: used interchangeably with
Application Server throughout this document.
EC: Edge Computing
Edge Hosting Environment: An environment providing support
required for Edge Application Server's
execution.
NOTE: The above terminologies are the same as
those used in 3GPP TR 23.758
Edge DC: Edge Data Center, which provides the Edge
Computing Hosting Environment. It might be co-
located with 5G Base Station and not only host
5G core functions, but also host frequently
used Edge server instances.
gNB next generation Node B
L-DN: Local Data Network
PSA: PDU Session Anchor (UPF)
SSC: Session and Service Continuity
UE: User Equipment
UPF: User Plane Function
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL",
"SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT
RECOMMENDED", "MAY", and "OPTIONAL" in this document are to
be interpreted as described in BCP 14 [RFC2119] [RFC8174]
when, and only when, they appear in all capitals, as shown
here.
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3. OSPF Extension for 5G EC
3.1. Solution Overview
From IP Layer, the Application Servers are identified by
their IP (ANYCAST) addresses. The 5G Edge Computing
controller or management system is aware of the ANYCAST
addresses of the Applications that need optimized
forwarding in 5G EC environment. The 5G Edge Computing
controller or management system can configure the ACLs to
filter out those applications on the routers adjacent to
the 5G PSA and the routers to which the Application Servers
are directly attached.
The proposed solution is for the routers, i.e. A-ER, that
have direct links, i.e. the stub links as described in
RFC2328, to the Application Servers to collect various
measurements about the Servers' running status [5G-EC-
Metrics] and advertise the metrics to other routers in 5G
EC LDN (Local Data Network).
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3.2. IP Layer Metrics to Gauge Application Behavior
There are many available network techniques and protocols
to optimize forwarding or ensuring QoS for applications,
such as DSCP/DiffServ, Traffic Engineered (TE) solutions,
Segment Routing, etc. But the reality is that most
application servers don't expose their internal logics to
network operators. Their communications are generally
encrypted. Most of them do not even respond to PING or ICMP
messages initiated by routers or network gears.
[5G-EC-Metrics] describes the IP Layer Metrics that can
gauge the application servers running status and
environment:
- IP-Layer Metric for App Server Load Measurement:
The Load Measurement to an App Server is a weighted
combination of the number of packets/bites to the App
Server and the number of packets/bytes from the App
Server which are collected by the A-ER to which the App
Server is directly attached.
The A-ER is configured with an ACL that can filter out
the packets for the Application Server.
- Capacity Index
Capacity Index is used to differentiate the running
environment of the application server. Some data centers
can have hundreds, or thousands, of servers behind an
Application Server's App Layer Load Balancer that is
reachable from external world. Other data centers can
have very small number of servers for the application
server. "Capacity Index", which is a numeric number, is
used to represent the capacity of the application server
in a specific location.
- Site preference index:
[IPv6-StickyService] describes a scenario that some
sites are more preferred for handling an application
server than others for flows from a specific UE.
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In this document, the term "Application Server Egress
Router" [A-ER] is used to describe the last router that an
Application Server is attached. For 5G EC environment, the
A-ER can be the gateway router to the EC DC where multiple
Application servers' instance are hosted.
From IP Layer, an Application Server is identified by its
IP (ANYCAST) Address. Those IP addresses are called the
Application Server IDs throughout this document.
3.3. To Equalize among Multiple ANYCAST Locations
The main benefit of using ANYCAST is to leverage the
network layer information to equalize the traffic among
multiple Application Server locations of the same
Application, which is identified by its ANYCAST addresses.
For 5G Edge Computing environment, the ingress routers to
the LDN needs to be notified of the Load Index and Capacity
Index of the App Servers at different EC data centers to
make the intelligent decision on where to forward the
traffic for the application from UEs.
[5G-EC-Metrics] describes the algorithms that can be used
by the routers directly attached to the 5G PSA to compare
the cost to reach the App Servers between the Site-i or
Site-j:
alpha*(LoadIndex-i*Beta-i) (1-alpha)*(Delay-i*gamma-i)
Cost=min(--------------- ---------- + -----------------------------)
(LoadIndex-j * Beta-j) ( Delay-j *gamm-j)
LoadIndex-i: weighted combination of the total bytes
(or/and packets) sent to/received from the Application
Server at Site-i during a fixed time period.
Beta-i (larger value means higher capacity): capacity
index at the site i.
Delay-i: Network latency measurement (RTT) to the A-ER
that has the Application Server attached at the site-i.
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gamma (larger value means higher preference): Network
Preference index for the site-I.
alpha (a value between 0 and 1: Weight for load & site
Index. If smaller than 0.5, Network latency has more
influence; otherwise, Server load has more influence).
3.4. OSPF Protocol Extension to advertise Load & Capacity
Goal of the protocol extension:
- Primary goal: Propagate the Load Measurement Index for
the attached App Servers to other routers in the LDN.
- Secondary goal: Propagate the Capacity Index & Site
Preference Index to other routers in the LDN.
Capacity index & Site preference might be steadier for an
Application server in a data center. It is possible to
use network management channel to distribute those two
attributes. Therefore, it is the secondary goal.
The OSPF extension takes the approach of TE solution:
- Each mini-DC gateway router announces the stub networks
of the attached Server addresses with the Load Index Sub-
TLV.
Only need to advertise the addresses for the applications
that needs the network to optimize the forwarding.
Therefore, A-ER do not need to advertise all attached
subnets.
- Load Index and Capacity Index are encoded in a Sub-TLV
added to the LSA.
3.5. Reason for using IGP Based Solution:
For scenario of multiple mini data centers within one AS
domain, there are benefits of using IGP approach:
- Intermediate routers can forward packets optimally
because they can derive the load status for the
Application Servers at different data centers by the IGP
protocol,
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- the path to the expected destination may be more
accurate or shorter
- Can quickly converge on faulty links and routers
- When a mini data center has failures, all the
packets in the fly can be optimally forwarded to an
App Server in another DC.
- Doesn't need ingress node to establish tunnels with
egress nodes.
- The operations in this approach from users' point of view
may be simpler.
Drawback of using IGP:
- This approach might not suit well to multiple ISPs
networks.
Using BGP, such as community extension or Tunnel Encap
extension, approach may be better for the network
crossing multiple ISPs.
3.6. OSPF Extension Using TE Stub Link
A new link type in Link TLV of TE LSA is defined for the
stub links, in addition to the existing P2P and Multi-
Access link types. A Stub Link is the address to the
Application Server attached.
For a stub link, a Link TLV comprises a Link Type sub-TLV
with stub link type, a Link ID sub-TLV with the address of
the attached App Server (stub-link), Link Data Sub-TLV and
some new sub-TLVs, such as, Load measurement sub-TLV,
Capacity sub-TLV and Preference sub-TLV.
An example of Link TLV for a stub link is illustrated
below:
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0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type = 2 | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link type sub-TLV for stub link |
~ ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link ID sub-TLV for the Instance address |
~ ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link data sub-TLV for the mask of the AppServer address |
~ ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Load measurement sub-TLV |
~ ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Capability sub-TLV |
~ ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Preference sub-TLV |
~ ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The Type value of the Link Type sub-TLV for the stub link:
3 (to be assigned by IANA).
Note: [RFC3630] has specified: Type=1 for P2P and Type=2
used for Multiaccess.
The Link Data Sub-TLV for the stub network is defined as:
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type (TBD1) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| AppServer IP address mask |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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Load Measurement sub-TLV has the following format:
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type (TBD2) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Measurement Period |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| total number of packets to the AppServer |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| total number of packets from the AppServer |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| total number of bytes to the AppServer |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| total number of bytes from the AppServer |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Load measurement Sub-TLV:
Type=1: measurement of the packets towards the stub link
(i.e. towards the server instance);
Type=2: measurement of packets from the stub link (i.e.
from the server instance).
Measurement Period: A user specified period in seconds,
default is 3600 seconds.
The Capacity Index sub-TLV has the following format:
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type (TBD3) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Capacity Index |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The Preference Index sub-TLV has the following format:
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type (TBD4) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Preference Index |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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Note: "Capacity Index" and "Site preference" can be more
stable for each site. If those values are configured to
nodes, they might not need to be included in every OSPF
LSA.
3.7. Aggregated Link Cost Solution
Another solution is to reuse the field for link cost of a
stub link.
For a router with an Application Server directly attached,
its router LSA can contain a stub link for the App Server's
address [RFC2328]. This solution is using a formula to
calculate the aggregated cost value to the directly
attached App Server and assigned the cost value to the
Metric field of the stub link in the LSA in RFC2328.
The cost to the attached Application Server plays a
significant role on where the flows should be routed. See
Section 4 for soft anchoring a flow to a specific location
when the UEs move.
In this solution, the values of the Link ID, Link data and
link cost for the stub link are as follows:
- The Link ID is the IP address of the Application
Server,
- The Link Data is the network mask of the
Application Server address,
- The Link cost is the aggregated cost reach the
attached Application Server.
In this solution, every router connected to an Application
Server MUST use the same formula to compute the cost of the
Application Server.
No new protocol code point is needed.
The drawback of this solution is that Ingress router cannot
make differentiated forwarding for different applications
flows.
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4. Soft Anchoring of an ANYCAST Flow
This section describes a solution that can anchor an
application flow from a UE to a specific ANYCAST instance
even when the UE moves from one 5G Site to another. This
is called "Sticky Service" in the 3GPP Edge Computing
specification.
Lets' assume one application "App.net" is instantiated on
four servers that are attached to four different routers
R1, R2, R3, and R4 respectively. It is desired for packets
to the "App.net" from UE-1 to stick with one server, say
the App Server attached to R1, even when the UE moves from
one 5G site to another. When there is failure at R1 or the
Application Server attached to R1, the packets of the flow
"App.net" from UE-1 need to be forwarded to the
Application Server attached to R2, R3, or R4.
We call this kind of sticky service "Soft Anchoring",
meaning that anchoring to the site of R1 is preferred, but
other sites can be chosen when the preferred site
encounters failure.
Here is details of this solution:
- Assign a group of ANYCAST addresses to one
application. For example, "App.net" is assigned with
4 ANYCAST addresses, L1, L2, L3, and L4. L1/L2/L3/L4
represents the location preferred ANYCAST addresses.
- For the App.net Server attached to a router, the
router has four Stub links to the same Server, L1,
L2, L3, and L4 respectively. The cost to L1, L2, L3
and L4 is assigned differently for different routers.
For example,
o When attached to R1, the L1 has the lowest cost,
say 10, when attached to R2, R3, and R4, the L1
can have higher cost, say 30.
o ANYCAST L2 has the lowest cost when attached to
R2, higher cost when attached to R1, R3, R4
respectively.
o ANYCAST L3 has the lowest cost when attached to
R3, higher cost when attached to R1, R2, R4
respectively, and
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o ANYCAST L4 has the lowest cost when attached to
R4, higher cost when attached to R1, R2, R3
respectively
- When a UE queries for the "App.net" for the first
time, the DNS replies the location preferred ANYCAST
address, say L1, based on where the query is
initiated.
- When the UE moves from one 5G site-A to Site-B, UE
continues sending packets of the "App.net" to ANYCAST
address L1. The routers will continue sending packets
to R1 because the total cost for the App.net instance
for ANYCAST L1 is lowest at R1. If any failure occurs
making R1 not reachable, the packets of the "App.net"
from UE-1 will be sent to R2, R3, or R4 (depending on
the total cost to reach each of them).
If the Application Server supports the HTTP redirect, more
optimal forwarding can be achieved.
- When a UE queries for the "App.net" for the first
time, the global DNS replies the ANYCAST address G1,
which has the same cost regardless where the
Application Servers are attached.
- When the UE initiates the communication to G1, the
packets from the UE will be sent to the Application
Server that has the lowest cost, say the Server
attached to R1. The Application server is instructed
with HTTPs Redirect to respond back a location
specific URL, say App.net-Loc1. The client on the UE
will query the DNS for App.net-Loc1 and get the
response of ANYCAST L1. The subsequent packets from
the UE-1 for App.net are sent to L1.
5. Manageability Considerations
To be added.
6. Security Considerations
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To be added.
7. IANA Considerations
To be added.
8. References
8.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to
Indicate Requirement Levels", BCP 14, RFC 2119,
March 1997.
[RFC4364] E. rosen, Y. Rekhter, "BGP/MPLS IP Virtual
Private networks (VPNs)", Feb 2006.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase
in RFC 2119 Key Words", BCP 14, RFC 8174, DOI
10.17487/RFC8174, May 2017, <https://www.rfc-
editor.org/info/rfc8174>.
[RFC8200] s. Deering R. Hinden, "Internet Protocol, Version
6 (IPv6) Specification", July 2017
8.2. Informative References
[3GPP-EdgeComputing] 3GPP TR 23.748, "3rd Generation
Partnership Project; Technical Specification
Group Services and System Aspects; Study on
enhancement of support for Edge Computing in 5G
Core network (5GC)", Release 17 work in progress,
Aug 2020.
[5G-EC-Metrics] L. Dunbar, H. Song, J. Kaippallimalil, "IP
Layer Metrics for 5G Edge Computing Service",
draft-dunbar-ippm-5g-edge-compute-ip-layer-
metrics-00, work-in-progress, Oct 2020.
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[5G-StickyService] L. Dunbar, J. Kaippallimalil, "IPv6
Solution for 5G Edge Computing Sticky Service",
draft-dunbar-6man-5g-ec-sticky-service-00, work-
in-progress, Oct 2020.
[RFC5521] P. Mohapatra, E. Rosen, "The BGP Encapsulation
Subsequent Address Family Identifier (SAFI) and
the BGP Tunnel Encapsulation Attribute", April
2009.
[BGP-SDWAN-Port] L. Dunbar, H. Wang, W. Hao, "BGP Extension
for SDWAN Overlay Networks", draft-dunbar-idr-
bgp-sdwan-overlay-ext-03, work-in-progress, Nov
2018.
[SDWAN-EDGE-Discovery] L. Dunbar, S. Hares, R. Raszuk, K.
Majumdar, "BGP UPDATE for SDWAN Edge Discovery",
draft-dunbar-idr-sdwan-edge-discovery-00, work-
in-progress, July 2020.
[Tunnel-Encap] E. Rosen, et al "The BGP Tunnel
Encapsulation Attribute", draft-ietf-idr-tunnel-
encaps-10, Aug 2018.
9. Acknowledgments
Acknowledgements to Donald Eastlake for their review and
contributions.
This document was prepared using 2-Word-v2.0.template.dot.
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Internet-Draft OSPF Extension for 5G EC Service
Authors' Addresses
Linda Dunbar
Futurewei
Email: ldunbar@futurewei.com
HuaiMo Chen
Futurewei
Email: huaimo.chen@futurewei.com
Dunbar, et al. Expires April 26, 2021 [Page 20]