ALTO Working Group Young Lee
Dhruv Dhody
Qin Wu
Internet Draft Huawei
Intended status: standard Greg Bernstein
Grotto Networking
Tae Sang Choi
ETRI
October 21, 2013
ALTO Extensions to Support Application and Network Resource
Information Exchange for High Bandwidth Applications in TE networks
draft-lee-alto-app-net-info-exchange-04.txt
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Abstract
This draft proposes ALTO information model and protocol extensions to
support application and network resource information exchange for high
bandwidth applications in partially controlled and controlled
environments as part of the infrastructure to application information
exposure (i2aex) initiative.
Table of Contents
1. Introduction..................................................3
2. Problem Statement..............................................5
3. ALTO Constraints Filtering Extension Model.....................8
3.1. ALTO Query from Application Stratum to Network Stratum....8
3.2. ALTO Response from Network Stratum to Application Stratum10
3.3. Information Model of ALTO Query from Application Stratum to
Network Stratum...............................................10
3.4. Information Model of ALTO Response from Network Stratum to
Application Stratum...........................................11
3.5. ALTO Protocol Extension for Constraints Filtering Mechanism
..............................................................11
3.6. Multiple Service Class...................................13
3.6.1. Gold Service........................................13
3.6.2. Silver Service......................................15
3.6.3. Bronze Service......................................17
4. ALTO Protocol Extension for Graph Representation Mechanism....19
5. Summary and Conclusion........................................19
6. Security Considerations.......................................19
7. IANA Considerations...........................................19
8. References....................................................19
8.1. Informative References...................................19
Author's Addresses...............................................21
Intellectual Property Statement..................................21
Disclaimer of Validity...........................................22
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1. Introduction
This draft proposes ALTO information model and protocol extensions
to support application and network resource information exchange for
high bandwidth applications in partially controlled and controlled
environments as part of the infrastructure to application
information exposure (i2aex) initiative. The Controlled and
partially controlled ALTO environments referred to here are those
where general access to a specific ALTO server may be restricted to
a qualified list of clients.
This draft is build upon the previously introduced High Bandwidth
Use Cases [HighBW] and assumes that the network type carrying high
bandwidth is a Traffic-Engineered (TE) network. In [HighBW], we have
discussed two generic use cases that motivate the usefulness of
general interfaces for cross stratum optimization in the network
core. In our first use case, network resource usage became
significant due to the aggregation of many individually unique
client demands. In the second use case where data centers are
sending large amount of data with each other, bandwidth usage was
already significant enough to warrant the use of traffic engineered
"express lanes" (e.g., private line service). We introduce third use
case where inter-CDN providers may want to expose controlled network
resource usage information so that CDN applications (e.g., request
routing server) can utilize such information when appropriate
decisions (e.g., request routing redirection) are needed.
These use cases result in optimization problems that trade off
computational versus network costs and constraints. Both featured
use cases show the usefulness of an ALTO interface between the
application and network strata in optimizing the networked
applications.
In particular, this draft introduces: (i) enhanced constraints
filtering extensions to the ALTO protocol to reduce extraneous
information transfer and enhance information hiding from the
network's perspective; (ii) constrained cost graph mechanism
encoding that enables enhanced application traffic optimization that
was introduced by [HighBW].
In controlled and partially controlled environments in which
operators are willing to share additional network stratum resource
information such as bandwidth constraints or additional cost types
of topology (e.g., graph or summary), it can be useful to reduce the
amount of information transferred from the ALTO server to the ALTO
client.
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In considering information exchange between the application stratum
and the network stratum, especially from the network stratum to the
application stratum, the degree of information details is one of the
key concerns from the network providers' standpoint. On the one
hand, the network information has to be useful to the application;
on the other hand, the provided network information should hide
details about the network. In order to achieve these desired goals,
a simple enhancement to ALTO protocol would help significantly both
in reducing/filtering the amount of information and in increasing
the usefulness of the information from network to application.
Figure 1 shows ALTO Client-Server Architecture for Application-
Network information Exchange. Figure 1 shows that ALTO Client in the
application stratum can interface with ALTO Server in the network
stratum. With this architecture, a simple ALTO query mechanism from
application (via ALTO client) to network (via ALTO server) can be
implemented. According to this architecture, ALTO Client is assumed
to interact with the Application Orchestrator that has the knowledge
of the end-user (i.e., source) application requirement, Data Center
locations (i.e., destinations) and their resource information.
+--------------+
Resource Request | Application |
-----------> | Orchestrator |
+--------------+
| ALTO Client |
+--------------+
| /|\
ALTO Query | | ALTO Response
| |
| |
| |
\|/ |
+--------------+
| ALTO Server |
+--------------+
| Network |
| Orchestrator |
+--------------+
Figure 1 ALTO Client-Server Architecture for Application-Network
information Exchange
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The Application Orchestration functions depicted in Figure 1
interfacing data centers and end-users are out of the scope of this
document. For simplicity purpose, Figure 1 doesn't depict the
detailed relationship between ALTO client and server. In fact, both
client and server don't need to be in the same administration
boundary. It can be inter-operator and one to many relationships.
For example, in the cases of inter-CDN environment or generic multi-
domain environment, ALTO client represents a request routing server
of upstream CDN operator and it interacts with multiple downstream
CDN operators for their network resource information to make
efficient decisions for desired quality CDN services. Interaction
methods can either iterative or recursive. That is, ALTO client can
interact with multiple ALTO servers directly or ALTO client can
interact with one representative ALTO server and subsequent
interaction is done by the representative one to rest of ALTO
servers.
The organization of this document is as follows. Section 2 discusses
the ALTO architecture in the context of the application and network
strata interaction. Section 3 provides ALTO Information model and
protocol extension to support ALTO Constraints Filtering Mechanism.
Section 4 provides ALTO information model and the protocol extension
to support ALTO Constrained Cost Graph Mechanism.
2. Problem Statement
One critical issue in Application-Network information exchange in
ALTO is the amount of information exchanged between the application
and network strata. The information provided by network providers
can be not so useful to the application stratum unless such
information is abstracted into an appropriate level the that
application stratum can understand.
In partially controlled and controlled environments, network
providers can furnish appropriately abstracted and pruned
information to the application stratum with the cooperation of the
application stratum that can indicate some level of filtering and
pruning in its query.
To reduce extraneous information this draft allows for "filtering"
(or "pruning") of the following information in query/response of the
ALTO pull model:
. Topology Filtering - reduction of the results to only those
specified set of source(s) and destination(s) instead of the
entire network cost map. Note that this mechanism is not new
in the current ALTO protocol. In the context of application-
network information exchange, this topology filtering can be
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of a tremendous help in reducing the amount of data exchanged
between application and network.
. Multiple Service Class: ALTO server may provide multiple class
of service (Gold, Silver, or Bronze) and allow application to
request them accordingly.
. Multiple Cost: Alto server should be able to provide multiple
cost for a end to end path or abstract links in the graph.
. Optimization Criteria: The optimization criteria that the ALTO
server may use. For example, the criteria can be least number
of hops, least amount of delay (latency), etc.
. Constraint Filtering on paths or graphs (e.g., bandwidth,
latency, hop count, packet loss, etc.) - reduction of results
to only those that meet ALTO client specified cost bounds.
As discussed in [HighBW], in a controlled environment optimization
is significantly enhanced by sharing data related to bandwidth
constraints and additional cost measures [MultiCost], [TE-cost].
Such information may be considered sensitive to the network provider
just as application data, e.g., usage, demand, etc., may be
considered sensitive to an application provider. Section 3 provides
ALTO information model and protocol extensions to support topology,
multiple service class, constraints filtering mechanism.
Multiple Service Class (such as gold, silver and bronze services)
MAY be supported by the ALTO server. These service classes could
specify how the network is used (for ex exclusively reserved for the
application, protection provided etc). The Application should
further provision/reserve the network using some mechanisms which
are out of scope of this document. Some example of services: _
. Gold Service
This service could be used to specify that an exact path meeting the
application needs should be found. This path would be provisioned
and resources reserved exclusively for its use. An example could be
a private enterprise DC, which wish to offload to a public DC during
peak load.
. Silver Service
This service could be used to get the path properties between User
regions and DC. It could also specify some basic constraints that
all of them should satisfy. These paths would be provisioned and
resources maybe reserved. The Application may further assign end
user request to a particular DC by using the network information of
these paths. An example could be a gaming server geographically
dispersed at multiple DC. The end-user (gamer) could be dynamically
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assigned to the DC by looking at the past assignment, DC load and
network properties.
. Bronze Service
This service could be used to specify that a simple best effort path
should be found. This path would not be provisioned and resources
will not be reserved. The service could still return the network
information to the application which can use this information for DC
selection by taking network information into consideration. An
example could be a HD video service, which may use the network info
to select video source for the end user.
While it is important to reduce and filter the information amount
from network to application, for some applications that require
stringent QoS objectives (e.g., bandwidth and latency), simple
summary source-destination network resource information (i.e.,
summary form of topology) may not provide sufficient details to the
application stratum. For example, suppose that a multiple number of
large concurrent flows need to be scheduled from application to
network. In such a case, a summary form of network topology that
only shows source-destination bandwidth availability may not show
the bottleneck links over which more than one flow may compete for
the link bandwidth resource. This problem was indicated by [HighBW].
The following are the excerpts from [HighBW].
Consider the network shown in Figure 2, where DC indicates a
datacenter, ER an end user region (as in the end user aggregation
use case), N a switching node of some sort, and L a link. The link
capacities and costs are also shown on the figure as well as a cost
map between [ER1, ER2] and [DC1, DC2, DC3]. Since the network has a
tree structure (very unusual but easier to draw in ASCII art), the
cost map is unique.
As an illustration, assume that the maximum available capacity
between any individual end region and a data center is 5 units(i.e.,
L1=L2=L5=L6=5). However, link L3 (capacity 8 units) represents a
bottle neck to all the data centers (L3 is on all the paths to DC1,
DC2, or DC3 from all end regions, ER1 and ER2).
ALTO Cost Map is shown in the lower right corner of Figure 2. This
summary cost map does not provide enough details on the bottle
necks. The lower left corner shows Link Capacity Cost, from which
the bottle necks can be shown such that multi-flow commodity
scheduling can be made possible to avoid such bottle necks.
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,---. L1 +----+
( ER1 )`-. L5 .'|DC1 |
`---' `-._ ,-. / +----+
( N1) L3 ,-..'
.-'`-' `-.__ L4--(N3 )
,---. .' `-. ,-..--'' `-'`. +----+
( ER2 ).-'L2 (N2 ) L6 `-.|DC2 |
`---' `-'`-._ +----+
`-.
Link Capacity Cost `-._L7
L1 5 `-.
L2 5 `-._
L3 8 `-.
L4 6 ALTO Cost Map `-.+----+
L5 5 DC1 DC2 DC3 _ |DC3 |
L6 5 ER1 5 5 8 +----+
L7 10 ER2 6 6 9
Figure 2. Example network illustrating bottlenecks
With the current ALTO cost map structure, the least cost path from
ER1 would be either to DC1 or DC2. However, with the proposed
capacitated cost map, the connection from ER1 to DC3 could be a
better choice than the rest depending on the relative cost of
network resources to data center resources.
A more general and relatively efficient alternative is to provide
the requestor with a capacitated and multiply weighted graph that
approximates and abstracts the capabilities of the network as seen
by the source and destination location sets. This document provides
ALTO information model and protocol extensions to support the graph
model in Section 4.
3. ALTO Constraints Filtering Extension Model
3.1. ALTO Query from Application Stratum to Network Stratum
In order for the network stratum to provide its resource
information, the application stratum needs to provide the End Point
Cost Map to the network stratum. The End Point Cost Map should
include the following information at a minimum:
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. End Point Source Address(es) /* these are the respective
addresses of the nearest PE's to the user/client location */
. End Point Destination Address(es) /* these are the respective
addresses of the nearest PE's to a set of the candidate Data
Center locations that can provide service to the user request.
*/
Note that how ALTO client derives the End Point Source/Destination
addresses in terms of the nearest PE's is beyond the scope of this
document.
. Service-Class:= {gold, silver, bronze} /*the service class as
described in this document*/
. Cost Type:= 'routingcost' as defined by base specification.
Additional cost (ex. latency, hopcount) are defined in
[MultiCost] and [TE-cost].
. Cost Mode :={summary, graph} /* the cost map can be either a
summary form or a graph form */
o Cost Mode: summary
This cost mode is indicated by string 'summary'. This mode
indicates that the returned costs contain end-to-end
values which can be used by application stratum for better
selection of resources.
o Cost Mode: gragh
This cost mode is indicated by string 'gragh' in which
case an abstract topology is returned to the application.
. Constraints /* a set of constraints that apply to the requested
path summary or graph for filtering. For instance, constraints
can be like bandwidth greater than 'x', latency less than 'y',
hopcount less than 'z', packetloss less than 'a' etc. */
. Objective-function (or Optimization Criteria): The summary or
the graph should be computed based on optimizing which
parameter - IGP cost, latency, residual bandwidth, etc. This is
for future use.
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3.2. ALTO Response from Network Stratum to Application Stratum
In response to the ALTO Query from the Application Stratum, the
Network Stratum needs to provide the filtered Cost Map Data of the
feasible path found. The Filtered End Cost Map Data should include
the following information at a minimum:
. The list of feasible Source-Destination pair and its Cost Type
. For each feasible S-D pair, indicate the following as specified
in Section 3.4:
o Service Class;
o Cost Mode;
o Cost Type;
o Endpoint Cost Map Data
. Parameter Values /* indicate the actual values of each
constraint requested */
Note that in case of Graph, each S-D pair is the source of the
abstract link and the destination of the abstract link.
3.3. Information Model of ALTO Query from Application Stratum to
Network Stratum
Alto query:
Object{
TypedEndpointAddr Src<1...*>; /*atleast one source*/
TypedEndpointAddr Dsts<2...*>; /*atleast two destinations*/
}EndpointList;
Object{
ServiceClass service-class;
CostMode cost-mode;
CostType cost-type;
[JSONString constraints<0...*>; ]
[JSONString ObjectiveFunction]
EndpointList endpoints;
}EndpointCostMapReq;
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3.4. Information Model of ALTO Response from Network Stratum to
Application Stratum
Alto response:
Object-map{
JSONString costparam;
} EndpointCostParam ;
Object-map{
TypedEndpointAddr -> EndpointCostParam<1...*>;
} EndpointCosts ;
Object-map{
TypedEndpointAddr -> EndpointCosts;
} EndpointCostMapData ;
Object{
ServiceClass service-class;
CostMode cost-mode;
CostType cost-type;
[EndpointCostMapData map;]
}EndpointCostMapRsp;
The Alto response consist of map (EndpointCostMapData) which is map
containing the S-D pairs information. For each destination, its
parameters (rank, cost etc) is included using EndpointCostParam.
3.5. ALTO Protocol Extension for Constraints Filtering Mechanism
This section provides the ALTO protocol extensions based on the
information model discussed in Sections 3.3. and 3.4. The scenario
provided in this section is that the ALTO client in the Application
Stratum requests the summary cost map from the network with one
source and three destinations.
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In this particular example, the ALTO client requests the filtered
summary of the network path subject to: bandwidth >= 20, latency <
10, hop count < 5 and packet loss < 0.03.
The ALTO server provides the resulted network paths in summary.
POST /endpointcost/lookup HTTP/1.1
Host: alto.example.com
Content-Length: [TODO]
Content-Type: application/alto-csoendpointcostparams+json
Accept: application/alto-csoendpointsummary+json,application/alto-
error+json
{
"service-class" : "silver",
"cost-mode" : "summary",
"cost-type" : "routingcost",
"constraints": ["availbw gt 20", "delay lt 10", "hopcount lt 5",
"pktloss lt 0.03"],
"endpoints" : {
"srcs": [ "ipv4:192.0.2.2" ],
"dsts": [
"ipv4:192.0.2.89",
"ipv4:198.51.100.34",
"ipv4:203.0.113.45"
]
}
}
HTTP/1.1 200 OK
Content-Length: [TODO]
Content-Type: application/alto-csoendpointsummary+json
{
"meta" : {},
"data" : {
"service-class" : "silver",
"cost-mode" : "summary",
"cost-type" : "routingcost",
"map" : {
"ipv4:192.0.2.2": {
"ipv4:192.0.2.89" : [ "delay eq 5",
"hopcount eq 8", "pktloss eq 0.01", cost eq
100" ],
"ipv4:18.51.100.34" : [ "delay eq 9",
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"hopcount eq 10", "pktloss eq 0.02", cost
eq 120" ],
"ipv4:203.0.113.45" : [ "delay eq 40",
"hopcount eq 12", "pktloss eq 0.02", cost
eq 50" ]
}
}
}
}
3.6. Multiple Service Class
The examples of various class of service is as follows, note that
these examples are for illustrative purpose only.
3.6.1. Gold Service
As an example of a Gold service, consider a customer (say an
Enterprise Private DC) who pays Top-Dollor to setup network based on
the actual demand. The Path (maybe a TE LSP) would not be used by
any other customer / application giving guarantee of service and
best QoE to the application. The ALTO request/response may be used
first to get the network states and later the path may also be
provisioned by some mechanism which is out of scope of this
document.
In this example, the application may like to find out the ranking of
the destinations (DC) from the network point of view. It may further
set the filtering constraints for bandwidth (bw), delay etc. The
ALTO server first filter the destination that do not meet the
constraints, further it provides ranking information based on the
requested costtype.
Alto Request:
POST /endpointcost/lookup HTTP/1.1
Host: alto.example.com
Content-Length: [TODO]
Content-Type: application/alto-csoendpointcostparams+json
Accept: application/alto-
csoendpointsummary+json,application/alto-
error+json
{
"service-class" : "gold",
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"cost-mode" : "summary",
"cost-type" : "routingcost",
"constraints": ["availbwgt 20", "delay lt 10",
"pktloss lt 0.03", "jitter lt 10", "hopcount
lt 5" ],
"endpoints" : {
"srcs": [ "ipv4:192.0.2.2" ],
"dsts": [
"ipv4:192.0.2.89",
"ipv4:198.51.100.34",
"ipv4:203.0.113.45"
]
}
}
ALTO server would factor in the filtering constraints and provide
only the ranking information to the application.
Alto Response:
HTTP/1.1 200 OK
Content-Length: [TODO]
Content-Type: application/alto-csoendpointsummary+json
{
"meta" : {},
"data" : {
"service-class" : "gold",
"cost-mode" : "summary",
"cost-type" : "routingcost",
"map" : {
"ipv4:192.0.2.2": {
"ipv4:192.0.2.89" : [ "rank eq 3" ],
"ipv4:198.51.100.34" : [ "rank eq 1" ],
"ipv4:203.0.113.45" : [ "rank eq 2" ]
}
}
}
}
Note that above is just an example, a gold service may also choose to
get detailed end to end information or an abstract graph.
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3.6.2. Silver Service
As an example of a Silver service, consider a customer (say a Online
Gaming Company) which will pay flat subscription fees to connect end
user-regions to the DC hosting the online gaming servers.. In this
case during the setup phase a flat full mesh of paths are
established between the User regions and the Data Centers.
The Application gaming load balancer would handle the gaming end
user by allocating him to a particular DC (gaming server). The
reserved resources during admin setup are allocated to multiple end
user requests.
In this example, application may want to know the end to end
properties of the path between the user-regions and the DC. It may
further set the filtering constraints for bandwidth (bw), delay etc.
Alto Request:
POST /endpointcost/lookup HTTP/1.1
Host: alto.example.com
Content-Length: [TODO]
Content-Type: application/alto-csoendpointcostparams+json
Accept: application/alto-csoendpointsummary+json,application/alto-
error+json
{
"service-class" : "silver",
"cost-mode" : "summary",
"cost-type" : "routingcost",
"constraints": ["availbwgt 20", "delay lt 10",
"pktloss lt 0.03", "jitter lt 10", "hopcount
lt 5" ],
"endpoints" : {
"srcs": [
"ipv4:192.0.2.2",
"ipv4:192.0.2.10"
],
"dsts": [
"ipv4:192.0.2.89",
"ipv4:198.51.100.34",
"ipv4:203.0.113.45"
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]
}
}
ALTO server would factor in the filtering constraints and provide
the end to end cost parameters to the application.
Alto Response:
HTTP/1.1 200 OK
Content-Length: [TODO]
Content-Type: application/alto-csoendpointsummary+json
{
"meta" : {},
"data" : {
"service-class" : "silver",
"cost-mode" : "summary",
"cost-type" : "routingcost",
"map" : {
"ipv4:192.0.2.2": {
"ipv4:192.0.2.89" : [ "delay eq 5", "jitter eq 5",
"pktloss eq 0.01", "hopcount eq 8",
"cost eq 100" ],
"ipv4:198.51.100.34" : [ "delay eq 9", "jitter eq 3",
"pktloss eq 0.02", "hopcount eq 10",
"cost eq 500" ],
"ipv4:203.0.113.45" : [ "delay eq 4", "jitter eq 4",
"pktloss eq 0.02", "hopcount eq 12",
"cost eq 200" ]
}
"ipv4:192.0.2.10": {
"ipv4:192.0.2.89" : [ "delay eq 4", "jitter eq 4",
"pktloss eq 0.03", "hopcount eq 6",
"cost eq 300" ],
"ipv4:203.0.113.45" : [ "delay eq 6", "jitter eq 6",
"pktloss eq 0.04", "hopcount eq 8",
"cost eq 400"]
}
}
}
}
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Note that above is just an example, a silver service may also choose to
get an abstract graph in response.
3.6.3. Bronze Service
As an example of a Bronze service, consider a customer (say a Video
service) doesnt reserve resources but pays a small fees to get an
abstract view of the network. Best effort service, use IP best
effort path(instead of reserved paths used by gold, silver). The
application (global load balancer) could get the network abstract
topology and would further handle the end user request by allocating
them to a particular DC or CDN.
In this example, application may rely on the basic IP best effort
but would like to know the abstract topology that could be used by
the application to find out bottleneck etc. Note that no constraints
are passed in this example and graph is requested.
Alto Request:
POST /endpointcost/lookup HTTP/1.1
Host: alto.example.com
Content-Length: [TODO]
Content-Type: application/alto-csoendpointcostparams+json
Accept: application/alto-
csoendpointsummary+json,application/alto-
error+json
{
"service-class" : "bronze",
"cost-mode" : "graph",
"cost-type" : "routingcost",
"endpoints" : {
"srcs": [
"ipv4:192.0.2.2",
"ipv4:192.0.2.10" ],
"dsts": [
"ipv4:192.0.2.89",
"ipv4:198.51.100.34",
"ipv4:203.0.113.45"
]
}
}
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ALTO server would prepare an abstract network graph based on the
source(s) and destination(s). The graph may also include some
internal (maybe abstract) nodes (ex 192.0.2.20 and 192.0.2.30).
Alto Response:
HTTP/1.1 200 OK
Content-Length: [TODO]
Content-Type: application/alto-csoendpointsummary+json
{
"meta" : {},
"data" : {
"service-class" : "bronze",
"cost-mode" : "graph",
"cost-type" : "routingcost",
"map": {
"ipv4:192.0.2.2": {
"ipv4:192.0.2.20" : [ "delay eq 9", "jitter eq 2",
"pktloss eq 0.04", "availbw eq 20",
"cost eq 100" ]
}
"ipv4:192.0.2.20": {
"ipv4:192.0.2.89" : [ "delay eq 5", "jitter eq 2",
"pktloss eq 0.02", "availbw eq 30",
"cost eq 100" ],
"ipv4:198.51.100.34" : [ "delay eq 3", "jitter eq 2",
"pktloss eq 0.01", "availbw eq 50",
"cost eq 400" ]
}
"ipv4:192.0.2.10": {
"ipv4:192.0.2.30" : [ "delay eq 4", "jitter eq 2",
"pktloss eq 0.01", "availbw eq 60",
"cost eq 300" ]
}
"ipv4:192.0.2.30": {
"ipv4:203.0.113.45" : [ "delay eq 2", "jitter eq 2",
"pktloss eq 0.03", "availbw eq 10",
"cost eq 200" ]
}
}
}
Lee et al. Expires April 21, 2014 [Page 18]
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}
Note that above is just an example, a bronze service may also choose to
get end to end information instead of an abstract graph in response.
Note that the EndpointCostMapData can be used for both the Graph
representation as well as the end to end path.
4. ALTO Protocol Extension for Graph Representation Mechanism
The encoding details for graph representation mechanism are shown in
Section 3.6.3 where the use of graph in a Bronze service is
described.
5. Summary and Conclusion
TBD
6. Security Considerations
TBD
7. IANA Considerations
TBD
8. Acknowledgements
The authors would like to thank Richard Yang and Sabine Randriamasy
for many helpful comments that greatly improved the contents of this
draft.
9. References
9.1. Informative References
[HighBW] G. Bernstein and Y. Lee, "Use Cases for High Bandwidth
Query and Control of Core Networks," draft-bernstein-alto-
large-bandwidth-cases, work in progress.
[MultiCost] S. Randriamasy, Ed., "Multi-Cost ALTO," draft-
randriamasy-alto-multi-cost, work in progress.
Lee et al. Expires April 21, 2014 [Page 19]
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[TE-cost] Q. Wu, et. al. "JSON Format Extensions for Traffic
Engineering (TE) performance metrics in the ALTO
Information Resource Directory, draft-wu-alto-json-te,
work in progress.
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Author's Addresses
Young Lee
Huawei Technologies
1700 Alma Drive, Suite 500
Plano, TX 75075
USA
Phone: (972) 509-5599
Email: leeyoung@huawei.com
Dhruv Dhody
Huawei Technologies, India
Email: dhruv.dhody@huawei.com
Qin Wu
Huawei Technologies, China
Email: bill.wu@huawei.com
Greg M. Bernstein
Grotto Networking
Fremont California, USA
Phone: (510) 573-2237
Email: gregb@grotto-networking.com
Tae-Sang Choi
ETRI
161 Gajong-Dong, Yusong-Gu
Daejon, Republic of Korea
Phone: (8242) 860-5628
Email: choits@etri.re.kr
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