draft-ietf-rtcweb-stun-consent-freshness-13.txt   draft-ietf-rtcweb-stun-consent-freshness-14.txt 
RTCWEB M. Perumal RTCWEB M. Perumal
Internet-Draft Ericsson Internet-Draft Ericsson
Intended status: Standards Track D. Wing Intended status: Standards Track D. Wing
Expires: November 14, 2015 R. Ravindranath Expires: December 10, 2015 R. Ravindranath
T. Reddy T. Reddy
Cisco Systems Cisco Systems
M. Thomson M. Thomson
Mozilla Mozilla
May 13, 2015 June 8, 2015
STUN Usage for Consent Freshness STUN Usage for Consent Freshness
draft-ietf-rtcweb-stun-consent-freshness-13 draft-ietf-rtcweb-stun-consent-freshness-14
Abstract Abstract
To prevent sending excessive traffic to an endpoint, periodic consent To prevent WebRTC applications, such as browsers, from launching
needs to be obtained from that remote endpoint. attacks by sending media to unwilling victims, periodic consent to
send needs to be obtained from remote endpoints.
This document describes a consent mechanism using a new Session This document describes a consent mechanism using a new Session
Traversal Utilities for NAT (STUN) usage. Traversal Utilities for NAT (STUN) usage.
Status of This Memo Status of This Memo
This Internet-Draft is submitted in full conformance with the This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79. provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/. Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on November 14, 2015. This Internet-Draft will expire on December 10, 2015.
Copyright Notice Copyright Notice
Copyright (c) 2015 IETF Trust and the persons identified as the Copyright (c) 2015 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Applicability . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Design Considerations . . . . . . . . . . . . . . . . . . . . 3 3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
4. Solution . . . . . . . . . . . . . . . . . . . . . . . . . . 3 4. Design Considerations . . . . . . . . . . . . . . . . . . . . 3
4.1. Expiration of Consent . . . . . . . . . . . . . . . . . . 3 5. Solution . . . . . . . . . . . . . . . . . . . . . . . . . . 4
4.2. Immediate Revocation of Consent . . . . . . . . . . . . . 5 5.1. Expiration of Consent . . . . . . . . . . . . . . . . . . 4
5. DiffServ Treatment for Consent . . . . . . . . . . . . . . . 6 5.2. Immediate Revocation of Consent . . . . . . . . . . . . . 6
6. DTLS applicability . . . . . . . . . . . . . . . . . . . . . 6 6. DiffServ Treatment for Consent . . . . . . . . . . . . . . . 7
7. API Recommendations . . . . . . . . . . . . . . . . . . . . . 6 7. DTLS applicability . . . . . . . . . . . . . . . . . . . . . 7
8. Security Considerations . . . . . . . . . . . . . . . . . . . 6 8. Security Considerations . . . . . . . . . . . . . . . . . . . 7
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 6 9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7
10. Acknowledgement . . . . . . . . . . . . . . . . . . . . . . . 7 10. Acknowledgement . . . . . . . . . . . . . . . . . . . . . . . 7
11. References . . . . . . . . . . . . . . . . . . . . . . . . . 7 11. References . . . . . . . . . . . . . . . . . . . . . . . . . 8
11.1. Normative References . . . . . . . . . . . . . . . . . . 7 11.1. Normative References . . . . . . . . . . . . . . . . . . 8
11.2. Informative References . . . . . . . . . . . . . . . . . 7 11.2. Informative References . . . . . . . . . . . . . . . . . 8
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 8 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 9
1. Introduction 1. Introduction
To prevent attacks on peers, endpoints have to ensure the remote peer To prevent attacks on peers, endpoints have to ensure the remote peer
is willing to receive traffic. This is performed both when the is willing to receive traffic. This is performed both when the
session is first established to the remote peer using Interactive session is first established to the remote peer using Interactive
Connectivity Establishment ICE [RFC5245] connectivity checks, and Connectivity Establishment ICE [RFC5245] connectivity checks, and
periodically for the duration of the session using the procedures periodically for the duration of the session using the procedures
defined in this document. defined in this document.
skipping to change at page 2, line 49 skipping to change at page 2, line 50
initial consent to send by performing STUN connectivity checks. This initial consent to send by performing STUN connectivity checks. This
document describes a new STUN usage with exchange of request and document describes a new STUN usage with exchange of request and
response messages that verifies the remote peer's ongoing consent to response messages that verifies the remote peer's ongoing consent to
receive traffic. This consent expires after a period of time and receive traffic. This consent expires after a period of time and
needs to be continually renewed, which ensures that consent can be needs to be continually renewed, which ensures that consent can be
terminated. terminated.
This document defines what it takes to obtain, maintain, and lose This document defines what it takes to obtain, maintain, and lose
consent to send. Consent to send applies to a single 5-tuple. How consent to send. Consent to send applies to a single 5-tuple. How
applications react to changes in consent is not described in this applications react to changes in consent is not described in this
document. document. The consent mechanism does not update the ICE procedures
defined in [RFC5245].
Consent is obtained only by full ICE implementations. An ICE-lite Consent is obtained only by full ICE implementations. An ICE-lite
implementation will not generate consent checks, but will just agent (as defined in Section 2.7 of [RFC5245]) does not generate
respond to consent checks it receives. No changes are required to connectivity checks or run the ICE state machine. An ICE-lite agent
ICE-lite implementations in order to respond to consent checks, as does not generate consent checks, it will only respond to any checks
they are processed as normal ICE connectivity checks. that it receives. No changes are required to ICE-lite
implementations in order to respond to consent checks, as they are
processed as normal ICE connectivity checks.
2. Terminology 2. Applicability
This document defines what it takes to obtain, maintain, and lose
consent to send using ICE. Verification of peer consent before
sending traffic is necessary in deployments like WebRTC to ensure
that a malicious JavaScript cannot use the browser as a platform for
launching attacks. Section 4.4 and Section 5.3 of
[I-D.ietf-rtcweb-security-arch] further explains the value of
obtaining and maintaining consent.
Other Applications that have similar security requirements to verify
peer's consent before sending non-ICE packets can use the consent
mechanism described in this document. The mechanism of how
applications are made aware of consent expiration is outside the
scope of the document.
3. Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119]. document are to be interpreted as described in [RFC2119].
Consent: The mechanism of obtaining permission to send to a remote Consent: The mechanism of obtaining permission from the remote
transport address. Initial consent is obtained using ICE. endpoint to send non-ICE traffic to a remote transport address.
Consent is obtained using ICE.
Consent Freshness: Maintaining and renewing consent over time. Consent Freshness: Maintaining and renewing consent over time.
Transport Address: The remote peer's IP address and UDP or TCP port Transport Address: The remote peer's IP address and UDP or TCP port
number. number.
3. Design Considerations 4. Design Considerations
Although ICE requires periodic keepalive traffic to keep NAT bindings Although ICE requires periodic keepalive traffic to keep NAT bindings
alive (Section 10 of [RFC5245], [RFC6263]), those keepalives are sent alive (Section 10 of [RFC5245], [RFC6263]), those keepalives are sent
as STUN Indications which are send-and-forget, and do not evoke a as STUN Indications which are send-and-forget, and do not evoke a
response. A response is necessary for consent to continue sending response. A response is necessary for consent to continue sending
traffic. Thus, we need a request/response mechanism for consent traffic. Thus, we need a request/response mechanism for consent
freshness. ICE can be used for that mechanism because ICE freshness. ICE can be used for that mechanism because ICE
implementations are already required to continue listening for ICE implementations are already required to continue listening for ICE
messages, as described in section 10 of [RFC5245]. If consent is messages, as described in Section 10 of [RFC5245]. STUN binding
performed then there is no need to send keepalive messages. requests sent for consent freshness also serve the keepalive purpose
(i.e to keep NAT bindings alive). Because of that, dedicated
keepalives (e.g. STUN Binding Indications) are not sent on candidate
pairs where consent requests are sent, in accordance with
Section 20.2.3 of [RFC5245].
4. Solution When Secure Real-time Transport Protocol (SRTP) is used, the
following considerations are applicable. SRTP is encrypted and
authenticated with symmetric keys; that is, both sender and receiver
know the keys. With two party sessions, receipt of an authenticated
packet from the single remote party is a strong assurance the packet
came from that party. However, when a session involves more than two
parties, all of whom know each other's keys, any of those parties
could have sent (or spoofed) the packet. Such shared key
distributions are possible with some MIKEY [RFC3830] modes, Security
Descriptions [RFC4568], and EKT [I-D.ietf-avtcore-srtp-ekt]. Thus,
in such shared keying distributions, receipt of an authenticated SRTP
packet is not sufficient to verify consent.
There are two ways consent to send traffic is revoked: expiration of The mechanism proposed in the document is an optional extension to
consent and immediate revocation of consent, which are discussed in the ICE protocol, it can be deployed at one end of the two-party
the following sections. communication session without impact on the other party.
4.1. Expiration of Consent 5. Solution
A full ICE implementation performs consent freshness test using STUN Initial consent to send traffic is obtained using ICE [RFC5245]. An
request/response as described below: endpoint gains consent to send on a candidate pair when the pair
enters the Succeeded ICE state. This document establishes a 30
second expiry time on consent. 30 seconds was chosen to balance the
need to minimize the time taken to respond to a loss of consent with
the desire to reduce the occurrence of spurious failures.
An endpoint MUST NOT send data other than paced STUN connectivity ICE does not identify when consent to send traffic ends. This
checks or responses toward any transport address unless the receiving document describes two ways in which consent to send ends: expiration
endpoint consents to receive data. That is, no application data of consent and immediate revocation of consent, which are discussed
(e.g., RTP or DTLS) can be sent until consent is obtained. After a in the following sections.
successful ICE connectivity check on a particular transport address,
consent MUST be maintained following the procedure described in this 5.1. Expiration of Consent
document.
A full ICE implementation obtains consent to send using ICE. After a
successful ICE connectivity check on a particular transport address
(i.e., a candidate pair has been marked as Succeeded), consent MUST
be maintained following the procedure described in this document.
An endpoint MUST NOT send data other than the messages used to
establish consent unless the receiving endpoint has consented to
receive data. Connectivity checks that are paced as described in
Section 16 of [RFC5245] and responses to connectivity checks are
permitted. That is, no application data (e.g., RTP or Datagram
Transport Layer Security (DTLS)) can be sent until consent is
obtained.
Explicit consent to send is obtained and maintained by sending an Explicit consent to send is obtained and maintained by sending an
STUN binding request to the remote peer's transport address and STUN binding request to the remote peer's transport address and
receiving a matching, authenticated, non-error STUN binding response receiving a matching, authenticated, non-error STUN binding response
from the remote peer's transport address. These STUN binding from the remote peer's transport address. These STUN binding
requests and responses are authenticated using the same short-term requests and responses are authenticated using the same short-term
credentials as the initial ICE exchange. credentials as the initial ICE exchange.
Note: Although TCP has its own consent mechanism (TCP Note: Although TCP has its own consent mechanism (TCP
acknowledgements), consent is necessary over a TCP connection acknowledgements), consent is necessary over a TCP connection
because it could be translated to a UDP connection (e.g., because it could be translated to a UDP connection (e.g.,
[RFC6062]). [RFC6062]).
Initial consent to send traffic is obtained using ICE. Consent Consent expires after 30 seconds. That is, if a valid STUN binding
expires after 30 seconds. That is, if a valid STUN binding response response has not been received from the remote peer's transport
corresponding to any STUN request sent in the last 30 seconds has not address in 30 seconds, the endpoint MUST cease transmission on that
been received from the remote peer's transport address, the endpoint 5-tuple. STUN consent responses received after consent expiry do not
MUST cease transmission on that 5-tuple. STUN consent responses re-establish consent, and may be discarded or cause an ICMP error.
received after consent expiry do not re-establish consent, and may be
discarded or cause an ICMP error.
To prevent expiry of consent, a STUN binding request can be sent To prevent expiry of consent, a STUN binding request can be sent
periodically. To prevent synchronization of consent checks, each periodically. To prevent synchronization of consent checks, each
interval MUST be randomized from between 0.8 and 1.2 times the basic interval MUST be randomized from between 0.8 and 1.2 times the basic
period. Implementations SHOULD set a default interval of 5 seconds, period. Implementations SHOULD set a default interval of 5 seconds,
resulting in a period between checks of 4 to 6 seconds. resulting in a period between checks of 4 to 6 seconds.
Implementations MUST NOT set the period between checks to less than 4
seconds. This timer is independent of the consent expiry timeout.
Each STUN binding request for consent MUST use a new Each STUN binding request for consent MUST use a new STUN transaction
cryptographically strong [RFC4086] STUN transaction ID. Each STUN identifier for every consent binding request, as described in
binding requests for consent is transmitted once only. Hence, the Section 6 of [RFC5389]. Each STUN binding request for consent is
sender cannot assume that it will receive a response for each consent transmitted once only. A sender therefore cannot assume that it will
request, and a response might be for a previous request (rather than receive a response for every consent request, and a response might be
for the most recently sent request). Consent expiration causes for a previous request (rather than for the most recently sent
immediate termination of all outstanding STUN consent transactions. request).
Each STUN transaction is maintained until one of the following
criteria is fulfilled:
o A STUN response associated with the transaction is received; or
o A STUN response associated to a newer transaction is received. An endpoint SHOULD await a binding response for each request it sends
for a time based on the estimated round-trip time (RTT) (see
Section 7.2.1 of [RFC5389]) with an allowance for variation in
network delay. The RTT value can be updated as described in
[RFC5389]. All outstanding STUN consent transactions for a candidate
pair MUST be discarded when consent expires.
To meet the security needs of consent, an untrusted application To meet the security needs of consent, an untrusted application
(e.g., JavaScript or signaling servers) MUST NOT be able to obtain or (e.g., JavaScript or signaling servers) MUST NOT be able to obtain or
control the STUN transaction ID, because that enables spoofing of control the STUN transaction identifier, because that enables
STUN responses, falsifying consent. spoofing of STUN responses, falsifying consent.
To prevent attacks on the peer during ICE restart, an endpoint that To prevent attacks on the peer during ICE restart, an endpoint that
continues to send traffic on the previously validated candidate pair continues to send traffic on the previously validated candidate pair
during ICE restart MUST continue to perform consent freshness on that during ICE restart MUST continue to perform consent freshness on that
candidate pair as described earlier. candidate pair as described earlier.
While TCP affords some protection from off-path attackers ([RFC5961], While TCP affords some protection from off-path attackers ([RFC5961],
[RFC4953]), there is still a risk an attacker could cause a TCP [RFC4953]), there is still a risk an attacker could cause a TCP
sender to send forever by spoofing ACKs. To prevent such an attack, sender to send forever by spoofing ACKs. To prevent such an attack,
consent checks MUST be performed over all transport connections, consent checks MUST be performed over all transport connections,
including TCP. In this way, an off-path attacker spoofing TCP including TCP. In this way, an off-path attacker spoofing TCP
segments can not cause a TCP sender to send once the consent timer segments cannot cause a TCP sender to send once the consent timer
expires (30 seconds). expires (30 seconds).
An endpoint that is not sending any application data does not need to An endpoint that is not sending any application data does not need to
maintain consent. However, not sending any traffic could cause NAT maintain consent. However, not sending any traffic could cause NAT
or firewall mappings to expire. Furthermore, having one peer unable or firewall mappings to expire. Furthermore, having one peer unable
to send is detrimental to many protocols. Absent better information to send is detrimental to many protocols. Absent better information
about the network, if an endpoint needs to ensure its NAT or firewall about the network, if an endpoint needs to ensure its NAT or firewall
mappings do not expire, it can be done using keepalive or other mappings do not expire, it can be done using keepalive or other
techniques (see Section 10 of [RFC5245] and see [RFC6263]). techniques (see Section 10 of [RFC5245] and see [RFC6263]).
After consent is lost for any reason, the same ICE credentials MUST After consent is lost, the same ICE credentials MUST NOT be used on
NOT be used on the affected 5-tuple again. That means that a new the affected 5-tuple again. That means that a new session, or an ICE
session, or an ICE restart, is needed to obtain consent to send. restart, is needed to obtain consent to send on the affected
candidate pair.
4.2. Immediate Revocation of Consent 5.2. Immediate Revocation of Consent
In some cases it is useful to signal that consent is terminated In some cases it is useful to signal that consent is terminated
rather than relying on a timeout. rather than relying on a timeout.
Consent for sending application data is immediately revoked by Consent for sending application data is immediately revoked by
receipt of an authenticated message that closes the connection (e.g., receipt of an authenticated message that closes the connection (e.g.,
a TLS fatal alert) or receipt of a valid and authenticated STUN a TLS fatal alert) or receipt of a valid and authenticated STUN
response with error code Forbidden (403). Note however that consent response with error code Forbidden (403). Note however that consent
revocation messages can be lost on the network, so an endpoint could revocation messages can be lost on the network, so an endpoint could
resend these messages, or wait for consent to expire. resend these messages, or wait for consent to expire.
skipping to change at page 6, line 5 skipping to change at page 7, line 8
TCP FIN) does not indicate revocation of consent. Thus, an endpoint TCP FIN) does not indicate revocation of consent. Thus, an endpoint
receiving an unauthenticated end-of-session message SHOULD continue receiving an unauthenticated end-of-session message SHOULD continue
sending media (over connectionless transport) or attempt to re- sending media (over connectionless transport) or attempt to re-
establish the connection (over connection-oriented transport) until establish the connection (over connection-oriented transport) until
consent expires or it receives an authenticated message revoking consent expires or it receives an authenticated message revoking
consent. consent.
Note that an authenticated SRTCP BYE does not terminate consent; it Note that an authenticated SRTCP BYE does not terminate consent; it
only indicates the associated SRTP source has quit. only indicates the associated SRTP source has quit.
5. DiffServ Treatment for Consent 6. DiffServ Treatment for Consent
It is RECOMMENDED that STUN consent checks use the same Diffserv It is RECOMMENDED that STUN consent checks use the same Diffserv
Codepoint markings as the ICE connectivity checks described in Codepoint markings as the ICE connectivity checks described in
Section 7.1.2.4 of [RFC5245] for a given 5-tuple. Section 7.1.2.4 of [RFC5245] for a given 5-tuple.
Note: It is possible that different Diffserv Codepoints are used by Note: It is possible that different Diffserv Codepoints are used by
different media over the same transport address different media over the same transport address
[I-D.ietf-tsvwg-rtcweb-qos]. Such a case is outside the scope of [I-D.ietf-tsvwg-rtcweb-qos]. Such a case is outside the scope of
this document. this document.
6. DTLS applicability 7. DTLS applicability
The DTLS applicability is identical to what is described in The DTLS applicability is identical to what is described in
Section 4.2 of [RFC7350]. Section 4.2 of [RFC7350].
7. API Recommendations
The W3C specification [W3C-WEBRTC] may provide an API hook that
generates an event when consent has expired for a given 5-tuple,
meaning that transmission of data has ceased. This could indicate
what application data is affected, such as media or data channels.
8. Security Considerations 8. Security Considerations
This document describes a security mechanism. This document describes a security mechanism, details of which are
mentioned in Section 4.1 and Section 4.2. Consent requires 96 bits
transaction ID to be uniformly and randomly chosen from the interval
0 .. 2**96-1, and be cryptographically strong. This is good enough
security against an off-path attacker replaying old STUN consent
responses. Consent Verification to avoid attacks using a browser as
an attack platform against machines is discussed in Sections 3.3 and
4.2 of [I-D.ietf-rtcweb-security].
The security considerations discussed in [RFC5245] should also be The security considerations discussed in [RFC5245] should also be
taken into account. taken into account.
SRTP is encrypted and authenticated with symmetric keys; that is,
both sender and receiver know the keys. With two party sessions,
receipt of an authenticated packet from the single remote party is a
strong assurance the packet came from that party. However, when a
session involves more than two parties, all of whom know each others
keys, any of those parties could have sent (or spoofed) the packet.
Such shared key distributions are possible with some MIKEY [RFC3830]
modes, Security Descriptions [RFC4568], and EKT
[I-D.ietf-avtcore-srtp-ekt]. Thus, in such shared keying
distributions, receipt of an authenticated SRTP packet is not
sufficient to verify consent.
9. IANA Considerations 9. IANA Considerations
This document does not require any action from IANA. This document does not require any action from IANA.
10. Acknowledgement 10. Acknowledgement
Thanks to Eric Rescorla, Harald Alvestrand, Bernard Aboba, Magnus Thanks to Eric Rescorla, Harald Alvestrand, Bernard Aboba, Magnus
Westerland, Cullen Jennings, Christer Holmberg, Simon Perreault, Paul Westerland, Cullen Jennings, Christer Holmberg, Simon Perreault, Paul
Kyzivat, Emil Ivov, Jonathan Lennox, Inaki Baz Castillo, Rajmohan Kyzivat, Emil Ivov, Jonathan Lennox, Inaki Baz Castillo, Rajmohan
Banavi and Christian Groves for their valuable inputs and comments. Banavi, Christian Groves, Meral Shirazipour and David Black for their
Thanks to Christer Holmberg for doing a through review. valuable inputs and comments. Thanks to Christer Holmberg for doing
a thorough review.
11. References 11. References
11.1. Normative References 11.1. Normative References
[I-D.ietf-rtcweb-security]
Rescorla, E., "Security Considerations for WebRTC", draft-
ietf-rtcweb-security-08 (work in progress), February 2015.
[I-D.ietf-rtcweb-security-arch]
Rescorla, E., "WebRTC Security Architecture", draft-ietf-
rtcweb-security-arch-11 (work in progress), March 2015.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997. Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC4086] Eastlake, D., Schiller, J., and S. Crocker, "Randomness
Requirements for Security", BCP 106, RFC 4086, June 2005.
[RFC5245] Rosenberg, J., "Interactive Connectivity Establishment [RFC5245] Rosenberg, J., "Interactive Connectivity Establishment
(ICE): A Protocol for Network Address Translator (NAT) (ICE): A Protocol for Network Address Translator (NAT)
Traversal for Offer/Answer Protocols", RFC 5245, April Traversal for Offer/Answer Protocols", RFC 5245, April
2010. 2010.
[RFC5389] Rosenberg, J., Mahy, R., Matthews, P., and D. Wing,
"Session Traversal Utilities for NAT (STUN)", RFC 5389,
October 2008.
[RFC6263] Marjou, X. and A. Sollaud, "Application Mechanism for [RFC6263] Marjou, X. and A. Sollaud, "Application Mechanism for
Keeping Alive the NAT Mappings Associated with RTP / RTP Keeping Alive the NAT Mappings Associated with RTP / RTP
Control Protocol (RTCP) Flows", RFC 6263, June 2011. Control Protocol (RTCP) Flows", RFC 6263, June 2011.
11.2. Informative References 11.2. Informative References
[I-D.ietf-avtcore-srtp-ekt] [I-D.ietf-avtcore-srtp-ekt]
Mattsson, J., McGrew, D., and D. Wing, "Encrypted Key Mattsson, J., McGrew, D., and D. Wing, "Encrypted Key
Transport for Secure RTP", draft-ietf-avtcore-srtp-ekt-03 Transport for Secure RTP", draft-ietf-avtcore-srtp-ekt-03
(work in progress), October 2014. (work in progress), October 2014.
[I-D.ietf-rtcweb-overview]
Alvestrand, H., "Overview: Real Time Protocols for
Browser-based Applications", draft-ietf-rtcweb-overview-13
(work in progress), November 2014.
[I-D.ietf-tsvwg-rtcweb-qos] [I-D.ietf-tsvwg-rtcweb-qos]
Dhesikan, S., Jennings, C., Druta, D., Jones, P., and J. Dhesikan, S., Jennings, C., Druta, D., Jones, P., and J.
Polk, "DSCP and other packet markings for RTCWeb QoS", Polk, "DSCP and other packet markings for RTCWeb QoS",
draft-ietf-tsvwg-rtcweb-qos-03 (work in progress), draft-ietf-tsvwg-rtcweb-qos-03 (work in progress),
November 2014. November 2014.
[RFC3830] Arkko, J., Carrara, E., Lindholm, F., Naslund, M., and K. [RFC3830] Arkko, J., Carrara, E., Lindholm, F., Naslund, M., and K.
Norrman, "MIKEY: Multimedia Internet KEYing", RFC 3830, Norrman, "MIKEY: Multimedia Internet KEYing", RFC 3830,
August 2004. August 2004.
skipping to change at page 8, line 24 skipping to change at page 9, line 20
2010. 2010.
[RFC6062] Perreault, S. and J. Rosenberg, "Traversal Using Relays [RFC6062] Perreault, S. and J. Rosenberg, "Traversal Using Relays
around NAT (TURN) Extensions for TCP Allocations", RFC around NAT (TURN) Extensions for TCP Allocations", RFC
6062, November 2010. 6062, November 2010.
[RFC7350] Petit-Huguenin, M. and G. Salgueiro, "Datagram Transport [RFC7350] Petit-Huguenin, M. and G. Salgueiro, "Datagram Transport
Layer Security (DTLS) as Transport for Session Traversal Layer Security (DTLS) as Transport for Session Traversal
Utilities for NAT (STUN)", RFC 7350, August 2014. Utilities for NAT (STUN)", RFC 7350, August 2014.
[W3C-WEBRTC]
Bergkvist, A., Burnett, D., Narayanan, A., and C.
Jennings, "WebRTC 1.0: Real-time Communication Between
Browsers", february 2015.
Authors' Addresses Authors' Addresses
Muthu Arul Mozhi Perumal Muthu Arul Mozhi Perumal
Ericsson Ericsson
Ferns Icon Ferns Icon
Doddanekundi, Mahadevapura Doddanekundi, Mahadevapura
Bangalore, Karnataka 560037 Bangalore, Karnataka 560037
India India
Email: muthu.arul@gmail.com Email: muthu.arul@gmail.com
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