BGP NLRI App Meta Data for 5G Edge Computing Service
draft-dunbar-idr-5g-edge-compute-app-meta-data-00
The information below is for an old version of the document.
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|---|---|---|---|
| Authors | Linda Dunbar , Kausik Majumdar | ||
| Last updated | 2020-10-31 | ||
| Replaced by | draft-dunbar-idr-5g-edge-service-metadata | ||
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draft-dunbar-idr-5g-edge-compute-app-meta-data-00
Network Working Group L. Dunbar
Internet Draft Futurewei
Intended status: Standard K. Majumdar
Expires: April 31, 2021 CommScope
October 31, 2020
BGP NLRI App Meta Data for 5G Edge Computing Service
draft-dunbar-idr-5g-edge-compute-app-meta-data-00
Abstract
This draft describes a new BGP Network Layer Reachability
Information (BGP NLRI) Path Attribute, AppMetaData, that can
distribute the 5G Edge Computing App running status and
environment, so that other routers in the 5G Local Data Network
can make intelligent decision on optimized forwarding of flows
from UEs. The goal is to improve latency and performance for 5G
Edge Computing services.
The extension enables a feature, called soft anchoring, which
makes one Edge Computing Server at one 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.
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79. This document may not be
modified, and derivative works of it may not be created, except
to publish it as an RFC and to translate it into languages other
than English.
Internet-Drafts are working documents of the Internet
Engineering Task Force (IETF), its areas, and its working
groups. Note that other groups may also distribute working
documents as Internet-Drafts.
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Table of Contents
1. Introduction................................................ 3
1.1. 5G Edge Computing Background........................... 3
1.2. Problem#1: ANYCAST in 5G EC 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. Usage of App Meta Data for 5G Edge Computing................ 7
3.1. Overview............................................... 7
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3.2. IP Layer Metrics to Gauge Application Behavior......... 8
3.3. To Equalize among Multiple ANYCAST Locations........... 9
3.4. BGP Protocol Extension to advertise Load & Capacity... 10
3.5. Reason for using BGP Based Solution:.................. 10
4. The NLRI Path Attribute for App Meta Data.................. 10
4.1. Load Measurement sub-TLV format....................... 12
4.2. Capacity Index sub-TLV format......................... 13
4.3. The Site Preference Index sub-TLV format.............. 13
5. Soft Anchoring of an ANYCAST Flow.......................... 14
6. Manageability Considerations............................... 16
7. Security Considerations.................................... 16
8. IANA Considerations........................................ 16
9. References................................................. 16
9.1. Normative References.................................. 16
9.2. Informative References................................ 16
10. Acknowledgments........................................... 17
1. Introduction
This document describes a new BGP Network Layer Reachability
Information (BGP NLRI) Path Attribute, AppMetaData, that can
distribute the 5G Edge Computing App running status and
environment, so that other routers in the 5G Local Data Network
can make intelligent decision on optimized forwarding of flows
from UEs. The goal is to improve latency and performance for 5G
Edge Computing services.
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,
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which is the IP Networks 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 locations 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.
This draft describes the BGP UPDATE extension to allow the App
Servers Running status and environment to be included in the BGP
UPDATE messages, so that other routers can select more optimal
ANYCAST location based on the combination of network delay, the
App Server load index, the location capacity index and the
location preference.
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 lived, it is difficult for the
application controller to anticipate the move and adjust.
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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 needs 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 perspective, this whole group of servers are
considered as the Application server at the
location.
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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.
3. Usage of App Meta Data for 5G Edge Computing
3.1. 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
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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 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).
3.2. IP Layer Metrics to Gauge Application Behavior
[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.
gamma (larger value means higher preference): Network
Preference index for the site-I.
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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. BGP Protocol Extension to advertise Load & Capacity
Goal of the protocol extension:
- Propagate the Load Measurement Index for the attached App
Servers to other routers in the LDN.
- Propagate the Capacity Index &
- Propagate Site Preference Index.
The BGP extension is to add the Load Index Sub-TLV, Capacity
Sub-TLV, and the Site Preference Sub-TLV in the NLRI associated
with the routes.
3.5. Reason for using BGP Based Solution:
To Be Added
4. The NLRI Path Attribute for App Meta Data
The App Meta Data attribute is an optional transitive BGP Path
attribute to carry application specific data, such as running
status, capacity and site preference. Will need IANA to assign
a value as the type code of the attribute. The attribute is
composed of a set of Type-Length-Value (TLV) encodings. Each
TLV contains information corresponding to metrics to a specific
Application Server. An App Meta Data TLV, is structured as
shown in Figure 1:
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| AppMetaData Type (2 Octets) | Length (2 Octets) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| Value |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2: App Meta Data TLV Value Field
AppMetaData Type (2 octets): identifies a type of Application
related metadata. The field contains values from the IANA
Registry "BGP AppMetaData Types". To be added.
o Length (2 octets): the total number of octets of the value
field.
o Value (variable): comprised of multiple sub-TLVs.
Each sub-TLV consists of three fields: a 1-octet type, a 1-octet
or 2-octet length field (depending on the type), and zero or
more octets of value. A sub-TLV is structured as shown in
Figure 2:
+--------------------------------+
| Sub-TLV Type (1 Octet) |
+--------------------------------+
| Sub-TLV Length (1 or 2 Octets) |
+--------------------------------+
| Sub-TLV Value (Variable) |
+--------------------------------+
Figure 3: App Metadata Sub-TLV Value Field
o Sub-TLV Type (1 octet): each sub-TLV type defines a certain
property about the AppMetaData TLV that contains this sub-TLV.
The field contains values from the IANA Registry "BGP
AppMetaData Attribute Sub-TLVs".
o Sub-TLV Length (1 or 2 octets): the total number of octets
of the sub-TLV value field. The Sub-TLV Length field contains
1 octet if the Sub-TLV Type field contains a value in the
range from 0-127. The Sub-TLV Length field contains two octets
if the Sub-TLV Type field contains a value in the range from
128-255.
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o Sub-TLV Value (variable): encodings of the value field
depend on the sub-TLV type as enumerated above. The following
sub-sections define the encoding in detail.
4.1. Load Measurement sub-TLV format
Two types of Load Measurement Sub-TLVs are specified. One is to
carry the measurements of packets/bytes to/from the App Server
address, another one is to carry the aggregated cost Index based
on weighted combination of the collected measurements.
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 4: Load Measurement Sub-TLV
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Measurement Period |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Aggregated Load Index to reach the App Server |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 5: Aggregated Load Index Sub-TLV
Type= TBD2: measurements of packets/bytes to/from the App
Server address;
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Type =TBD3: Aggregated Load Measurement Index derived from the
Weighted combination of bytes/packets sent to/received from
the App server:
Index=w1*ToPackets+w2*FromPackes+w3*ToBytes+w4*FromBytes
Where w1+ w2+ w3+ w4 = 1 and 0< wi <1;
Measure Period: BGP Update period or user specified period
4.2. Capacity Index sub-TLV format
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 (TBD4) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Capacity Index |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Note: "Capacity Index" can be more stable for each site. If
those values are configured to nodes, they might not need to be
included in every BGP UPDATE.
4.3. The Site Preference Index sub-TLV format
The site Preference Index is used to achieve Soft Anchoring
[Section 5] an application flow from a UE to a specific location
when the UE moves from one 5G site to another.
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 (TBD5) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Preference Index |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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Note: "Site Preference Index" can be more stable for each site.
If those values are configured to nodes, they might not need to
be included in every BGP UPDATE.
5. Soft Anchoring of an ANYCAST Flow
"Sticky Service" in the 3GPP Edge Computing specification (3GPP
TR 23.748) requires a UE to a specific ANYCAST location when
the UE moves from one 5G Site to another.
"Soft Anchoring" is referring to forwarding the Application
flow from the UE to the a preferred location for the ANYCAST
address, when the preferred location is in good condition. But
if there is any failure at the preferred location, the
Application flow from the UE need to be forwarded to another
location that host the same application.
This section describes a solution that can softly anchor an
application flow from a UE to a preferred location.
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,
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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
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.
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6. Manageability Considerations
To be added.
7. Security Considerations
To be added.
8. IANA Considerations
To be added.
9. References
9.1. 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
9.2. 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.
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[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.
[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.
10. 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 AppMetaData NLRI for 5G EC Service
Authors' Addresses
Linda Dunbar
Futurewei
Email: ldunbar@futurewei.com
Kausik Majumdar
CommScope
350 W Java Drive, Sunnyvale, CA 94089
Email: kausik.majumdar@commscope.com
Dunbar, et al. Expires April 31, 2021 [Page 18]