Use cases of Application-aware
Networking (APN) in Edge ComputingChina MobileBeijing100053Chinaliupengyjy@chinamobile.comChina MobileBeijing100053Chinaduzongpeng@chinamobile.comHuaweiBeijing100053Chinapengshuping@huawei.comHuaweiBeijing100053Chinalizhenbin@huawei.com
Networking
Network Working GroupAPN;edge computingThe ever-emerging new services are imposing more and more highly
demanding requirements on the network. However, the current deployments
could not fully accommodate those requirements due to limited
capabilities. For example, it is difficult to utilize the traditional
centralized deployment mode to meet the low-latency demand of some
latency-sensitive applications. Moreover, the total amount of
centralized service data is growing exponentially, which brings great
pressure on the network bandwidth. There has been a clear trend that
decentralized sites comprising of computing and storage resources are
deployed at various locations to provide services. In particular, when
the sites are deployed at the network edge, i.e. the Edge Computing, it
can better handle the business needs of the users nearby, which provides
the possibilities to provide differentiated network and computing
services. In order to achieve the full benefits of the edge computing,
it actually implies a precondition that the network should be aware of
the applications' requirements in order to steer their traffic to the
network paths that can satisfy their requirements. Application-aware
networking (APN) aims to accommodate the edge services' needs, fully
releasing the benefits of the edge computing.This document describes the various application scenarios in edge
computing to which the APN can be beneficial, including augmented
reality, cloud gaming and remote control, which empowers the video
business, users interaction business and user-device interaction
business. In those scenarios, APN can identify the specific requirements
of edge computing applications on the network, process close to the
users, provide SLA guaranteed network services such as low latency and
high reliability.The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119.Edge computing is to deploy service sites near the user side to
provide users with better network and computing services. The services
of edge computing can not only be implemented in the edge data center,
but also be integrated in the network equipment, which brings the
possibility for the convergence of network and computing, and also puts
forward the requirements for the technology combining of different
industries. On the one hand, the demand of different applications for
the network need to be exposed; on the other hand, the network needs to
be aware of computing power and steers the traffic along the appropriate
path towards the suitable sites.The existing network can only identify the application demands in a
coarse granularity. When the application demand is high causing the
heavy network load, it usually fails to guarantee the latency and
reliability of the applications especially the mission-critical
applications. Application-aware networking (APN) faciliates service
provisioning in a fine granularity, and then either steer the
corresponding traffic onto the appropriate network path (if exist) that
can satisfy these requirements or establish an exclusive network path
which wouldn't be influenced by other applications' traffic flow.In a whole edge computing network, there are user terminal, edge
gateway and edge data center. The edge gateway can be the UPF In 5G
network. Edge data center is usually close to users and serves a limited
group of users, the network and computing tasks performed by edge
computing are more specific and customized. Both computing resources and
network resources need to be able to provide fine-grained service
guarantee. The goal of APN is to provide fine-grained network service,
including latency, jitter, reliability and others, which can be well
matched with edge computing.Appilication-aware networking includes the app-aware edge (APN-Edge),
app-aware process head-end (APN-Head), app-aware process mid-point
(APN-Midpoint) and app-aware process end-point (APN-Endpoint). A user's
request is sent from the client, and then passes through all the nodes
of the APN network to the server. The function of APN-Edge can be
deployed in the edge gateway, so the request traffic of client can be
distinguished by the edge gateway/APN-Edge and sent to the edge data
center through the APN. In some cases, the reply of the edge data center
will not return to the original client, and may be sent to another
client through the APN. The APN network can use the exsiting
technologies such as deterministic network, network slicing, SR policy,
etc. which could coordinate well with the APN-Edge to garantee the
network service by encapsulating the requirement information in the
packets.This section presents several typical scenarios which require edge
computing to interconnect and to co-ordinate with APN to meet the
service requirements and ensure user experience.Augmented reality is a relatively new application that promotes
the integration of real world information and virtual world
information content. It includes several technologies, such as track
registration, display, virtual object generation, interaction and
merging.AR gives users an immersive experience. It is widely used in the
consumer industry presently, and may also be applied in industrial
fields such as health care and education in the future. The general
process of AR / VR is as follows:* Image acquisition equipment (such as camera) collects image or
video information and sends it to data center.* Data center carries out identification, feature extraction and
template rendering, and sends them to AR terminal.* The AR terminal plays the synthesized information.Considering the user experience, AR usually needs a high
bandwidth of 100mbps due to multi-channel acquisition of image or
video data, and a low end-to-end latency less than 60ms. With
centralized deployment, the network transmission distance is too
long, so the latency demand can't be met; the large volume of
traffic load also imposes high challenge on the network
bandwidth.If the deployment mode of edge computing is adopted, the
following functions can be realized:* The collected image or video information can be encoded/decode
and compressed by the edge equipment to reduce the bandwidth
requirements of data transmission.* The edge data center can process the collected image or video
data nearby and send it to the AR terminal equipment, which reduces
the distance of network transmission and greatly reduces the
latency.Although edge computing can reduce the overall latency of
services and reduce the demand for network bandwidth, it still needs
differentiated network services to provide the ultimate guarantee
for application with high SLA requirements. APN can achieve:* Edge device obtains and encapsulates AR application feature
information and sends it to the headend node.* Headend node in the APN identifies the AR data flow and steers
it into a specific transmission path according to the demanded
bandwidth, latency and reliability.* Mid point in the APN forwards the data stream along the
specific path.* End point in the APN receives AR data stream and forwards it
either to Data Centre for processing or to the AR player for
playing.In the whole process, because APN identifies the traffic of AR
application, it can provide corresponding network services to
provide customized high reliability, low latency and other SLA
guarantee.Cloud gaming is to deploy the game application in the data
center, and realize the functions includes the logical process of
game command control, as well as the tasks of game acceleration,
video rendering and other tasks with high requirements for chips. In
this way, the terminal is a video player. Users can get a good game
experience without the support of high-end system and chips.Compared with the traditional game mode, there are several
advantages of cloud game, such as no installation, no upgrade, no
repair, quick to play and reduce the terminal cost, so it will have
stronger promotion.The biggest feature of cloud games is that users interact with
each other through the network. The general process is as
follows:* The data center sends game video streaming information to the
terminal, including game background picture, characters, etc.* The user makes corresponding operation instructions according
to the received game video stream information and sends them to the
data center.* The data center constantly updates the video stream and other
data of the game according to the user's operation instructions.Game users usually pursue consumption experience. Currently, most
users are willing to spend extra money in order to obtain better
user experience. Generally speaking, the network latency of game is
required to be less than 30ms. For competitive game, the latency
will be required to be less than 10ms, because professional players
usually can feel the millisecond level latency difference. With
centralized deployment, the network transmission distance is too
long, which is a huge challenge to the network load, so the latency
demand can't be met; the large volume of traffic load also imposes
high challenge on the network bandwidth.If the deployment of edge computing is adopted, the following
functions can be realized with the deployment of edge data
center:* The edge data center sends the game video stream information to
the terminal, and receives the user's control instruction
information for processing.* users can make corresponding operation instructions according
to the received video stream information, and get quick
response.Edge computing can reduce the latency of game data transmission
as a whole, but it should be noted that cloud games usually have
multiple players playing a game together, which requires the
deterministic latency of multi-party network path, which needs to be
realized with APN:* Multiple edge devices obtain and encapsulate cloud game
application feature information and send it to the head end
node.* Headend node in the APN identifies the data flow of cloud games
(maybe the same game), and steers it into a specific transmission
path according to its requirements for bandwidth, delay,
reliability, etc., which needs to ensure that the latency of
multi-user control instructions arriving at the edge data center is
consistent.* Midpoint in the APN forwards game data stream according to the
predetermined path.* The endpoint in the APN receives the cloud game data stream and
steers it either to the data center for processing the users’
control instruction or to the user for playing.The whole process requires APN not only to identify the cloud
game traffic and provide customized network forwarding services for
it, but also to ensure the deterministic latency of multi-user in
the same game and provide better game experience.Industrial remote control refers to the remote control of field
equipment in areas that are not convenient for manual field control,
such as high-temperature and high-risk areas. In the past, signaling
was usually transmitted through industrial private networks and
protocols. With the development of industrial Internet, the industry
also gradually has the demand of network interconnection. Its
network tends to adopt L3 protocol and flat architecture, which
makes it possible for cross distance remote control service.In the process of remote control, workers constantly make control
instructions according to the received image or video information of
field equipment, which requires interaction between personnel and
equipment through the network. Because the field environment that
needs remote control is generally poor, it is also a challenge for
the security of the operation equipment. If the latency is too large
or the reliability is not enough, it may cause the operation
failure, equipment damage and other serious consequences. Therefore,
the remote control service requires low latency and high
reliability. The general process of remote control is as
follows:* Field equipment (such as camera) collects image or video
information and sends it to data center.* The data center receives the field information of the equipment
and sends it to the workers in the office.* Workers send control instructions and control equipment
according to the received field information.Many industrial enterprises rent public cloud resources to
construct their own data center, but the long distance of network
transmission is not conducive to the timely transmission of image /
video data stream, which will cause large latency and packet
loss.If the deployment mode of edge computing is adopted, and the data
center and edge computing access equipment (such as gateway) are
deployed in a location or enterprise park close to the business
site, the following functions can be realized:* The collected image or video information can be encoded/
decoded and compressed by edge access equipment to reduce the
bandwidth requirements.* The control instruction information can be identified by the
edge equipment, so as to provide exclusive network transmission
service.* The forwarding path of image / video and control information is
shortened, which can greatly reduce the latency.Although edge computing can reduce the overall delay of services
and reduce the demand of network bandwidth, it still needs to
achieve differentiated network services through APN to provide the
ultimate network guarantee for the services with the highest network
requirements.For users, APN can realize those functions.* Edge device obtains and encapsulates the image or video
information of the remote field device, then sends it to the headend
node.* Headend in the APN identifies the information and steers the
flow into a specific transmission path according to its requirements
for bandwidth, delay, reliability, etc..* Midpoint in the APN forwards along the specific path.* Endpoint receives image or video data stream of field equipment
and forwards it to users.For field equipment, APN can realize those functions.* Edge device obtains and encapsulates the control instruction
information and sends it to the head end node.* Headend in the APN identifies the control data flow and steers
into a specific transmission path according to the demand for
bandwidth, latency and reliability.* Midpoint in the APN forwards along the specific path.* Endpoint receives control information and forwards to the field
equipment.In the whole process, APN identifies the traffic of remote
control service, which can provide customized high reliability, low
latency and other network guarantee.APN enables low latency and high reliability network services in
various edge computing scenarios such as AR, cloud gaming, remote
industrial control, etc.TBD.TBD.