DOTS T. Reddy
Internet-Draft D. Wing
Intended status: Standards Track P. Patil
Expires: August 12, 2016 M. Geller
Cisco
M. Boucadair
France Telecom
R. Moskowitz
HTT Consulting
February 9, 2016
Co-operative DDoS Mitigation
draft-reddy-dots-transport-02
Abstract
This document discusses mechanisms that a DOTS client can use, when
it detects a potential Distributed Denial-of-Service (DDoS) attack,
to signal that the DOTS client is under an attack or request an
upstream DOTS server to perform inbound filtering in its ingress
routers for traffic that the DOTS client wishes to drop. The DOTS
server can then undertake appropriate actions (including, blackhole,
drop, rate-limit, or add to watch list) on the suspect traffic to the
DOTS client, thus reducing the effectiveness of the attack.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
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This Internet-Draft will expire on August 12, 2016.
Copyright Notice
Copyright (c) 2016 IETF Trust and the persons identified as the
document authors. All rights reserved.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Notational Conventions . . . . . . . . . . . . . . . . . . . 3
3. Solution Overview . . . . . . . . . . . . . . . . . . . . . . 4
4. Happy Eyeballs . . . . . . . . . . . . . . . . . . . . . . . 5
5. Protocol for Signal Channel: HTTP REST . . . . . . . . . . . 7
5.1. Mitigation service request . . . . . . . . . . . . . . . 7
5.1.1. Convey DOTS signal . . . . . . . . . . . . . . . . . 7
5.1.2. Recall DOTS signal . . . . . . . . . . . . . . . . . 9
5.1.3. Retrieving DOTS signal . . . . . . . . . . . . . . . 9
5.2. REST . . . . . . . . . . . . . . . . . . . . . . . . . . 10
5.2.1. Filtering Rules . . . . . . . . . . . . . . . . . . . 11
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13
7. Security Considerations . . . . . . . . . . . . . . . . . . . 13
8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 14
9. References . . . . . . . . . . . . . . . . . . . . . . . . . 14
9.1. Normative References . . . . . . . . . . . . . . . . . . 14
9.2. Informative References . . . . . . . . . . . . . . . . . 15
Appendix A. BGP . . . . . . . . . . . . . . . . . . . . . . . . 16
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 16
1. Introduction
A distributed denial-of-service (DDoS) attack is an attempt to make
machines or network resources unavailable to their intended users.
In most cases, sufficient scale can be achieved by compromising
enough end-hosts and using those infected hosts to perpetrate and
amplify the attack. The victim in this attack can be an application
server, a client, a router, a firewall, or an entire network, etc.
The reader may refer, for example, to [REPORT] that reports the
following:
o Very large DDoS attacks above the 100 Gbps threshold are
experienced.
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o DDoS attacks against customers remain the number one operational
threat for service providers, with DDoS attacks against
infrastructures being the top concern for 2014.
o Over 60% of service providers are seeing increased demand for DDoS
detection and mitigation services from their customers (2014),
with just over one-third seeing the same demand as in 2013.
In a lot of cases, it may not be possible for an enterprise to
determine the cause for an attack, but instead just realize that
certain resources seem to be under attack. The document proposes
that, in such cases, the DOTS client just inform the DOTS server that
the enterprise is under a potential attack and that the DOTS server
monitor traffic to the enterprise to mitigate any possible attack.
This document also describes a means for an enterprise, which act as
DOTS clients, to dynamically inform its DOTS server of the IP
addresses or prefixes that are causing DDoS. A DOTS server can use
this information to discard flows from such IP addresses reaching the
customer network.
The proposed mechanism can also be used between applications from
various vendors that are deployed within the same network, some of
them are responsible for monitoring and detecting attacks while
others are responsible for enforcing policies on appropriate network
elements. This cooperations contributes to a ensure a highly
automated network that is also robust, reliable and secure. The
advantage of the proposed mechanism is that the DOTS server can
provide protection to the DOTS client from bandwidth-saturating DDoS
traffic.
How a DOTS server determines which network elements should be
modified to install appropriate filtering rules is out of scope. A
variety of mechanisms and protocols (including NETCONF) may be
considered to exchange information through a communication interface
between the server and these underlying elements; the selection of
appropriate mechanisms and protocols to be invoked for that
interfaces is deployment-specific.
Terminology and protocol requirements for co-operative DDoS
mitigation are obtained from [I-D.ietf-dots-requirements].
2. Notational Conventions
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 [RFC2119].
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3. Solution Overview
Network applications have finite resources like CPU cycles, number of
processes or threads they can create and use, maximum number of
simultaneous connections it can handle, limited resources of the
control plane, etc. When processing network traffic, such an
application uses these resources to offer its intended task in the
most efficient fashion. However, an attacker may be able to prevent
the application from performing its intended task by causing the
application to exhaust the finite supply of a specific resource.
TCP DDoS SYN-flood is a memory-exhaustion attack on the victim and
ACK-flood is a CPU exhaustion attack on the victim. Attacks on the
link are carried out by sending enough traffic such that the link
becomes excessively congested, and legitimate traffic suffers high
packet loss. Stateful firewalls can also be attacked by sending
traffic that causes the firewall to hold excessive state and the
firewall runs out of memory, and can no longer instantiate the state
required to pass legitimate flows. Other possible DDoS attacks are
discussed in [RFC4732].
In each of the cases described above, if a network resource detects a
potential DDoS attack from a set of IP addresses, the network
resource (DOTS client) informs its servicing router (DOTS relay) of
all suspect IP addresses that need to be blocked or black-listed for
further investigation. DOTS client could also specify protocols and
ports in the black-list rule. That DOTS relay in-turn propagates the
black-listed IP addresses to the DOTS server and the DOTS server
blocks traffic from these IP addresses to the DOTS client thus
reducing the effectiveness of the attack. The DOTS client
periodically queries the DOTS server to check the counters mitigating
the attack. If the DOTS client receives response that the counters
have not incremented then it can instruct the black-list rules to be
removed. If a blacklisted IPv4 address is shared by multiple
subscribers then the side effect of applying the black-list rule will
be that traffic from non-attackers will also be blocked by the access
network.
If a DOTS client cannot determine the IP address(s) that are causing
the attack, but is under an attack nonetheless, the DOTS client can
just notify the DOTS server that it is under a potential attack and
request that the DOTS server take precautionary measures to mitigate
the attack.
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4. Happy Eyeballs
If a DOTS server IPv4 path is working, but the DOTS server's IPv6
path is not working, a dual-stack DOTS client can experience
significant connection delay compared to an IPv4-only DOTS client.
The other problem is that if a middle box between the DOTS client and
server is configured to block UDP, DOTS client will fail to establish
DTLS session [RFC6347] with the DOTS server and will have to fall
back to TLS over TCP [RFC5246] incurring significant connection
delay. [I-D.ietf-dots-requirements] discusses that DOTS client and
server will have to support both connectionless and connection-
oriented protocols.
To overcome these connection setup problems, the DOTS client MUST try
connecting to the DOTS server using both IPv6 and IPv4, and MUST try
both DTLS over UDP and TLS over TCP in a fashion similar to the
"Happy Eyeballs" mechanism [RFC6555]. These connection attempts are
performed by the DOTS client when its initializes, and the client
uses that information for its subsequent alert to the server. In
order of preference (most preferred first), it is UDP over IPv6, UDP
over IPv4, TCP over IPv6, and finally TCP over IPv4, which adheres to
address preference order [RFC6724] and the DOTS preference that UDP
be used over TCP (to avoid TCP's head of line blocking).
TBD: How does the DOTS client discover the DOTS server (use DNS-SD) ?
DOTS client DOTS server
| |
|--DTLS ClientHello, IPv6 ---->X |
|--TCP SYN, IPv6-------------->X |
|--DTLS ClientHello, IPv4 ---->X |
|--TCP SYN, IPv4----------------------------------------->|
|--DTLS ClientHello, IPv6 ---->X |
|--TCP SYN, IPv6-------------->X |
|<-TCP SYNACK---------------------------------------------|
|--DTLS ClientHello, IPv4 ---->X |
|--TCP ACK----------------------------------------------->|
|<------------Establish TLS Session---------------------->|
|----------------DOTS signal----------------------------->|
| |
Figure 1: Happy Eyeballs
In the diagram above, the DOTS client sends two TCP SYNs and two DTLS
ClientHello messages at the same time over IPv6 and IPv4. In the
diagram, the IPv6 path is broken and UDP is dropped by a middle box
but has little impact to the DOTS client because there is no long
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delay before using IPv4 and TCP. The IPv6 path and UDP over IPv6 and
IPv4 is retried until the DOTS client gives up.
DOTS client and server can also use the following techniques to
reduce delay to convey DOTS signal:
o DOTS client can use (D)TLS session resumption without server-side
state [RFC5077] to resume session and convey the DOTS signal.
o TLS False Start [I-D.ietf-tls-falsestart] which reduces round-
trips by allowing the TLS second flight of messages
(ChangeCipherSpec) to also contain the DOTS signal.
o Cached Information Extension [I-D.ietf-tls-cached-info] which
avoids transmitting the server's certificate and certificate chain
if the client has cached that information from a previous TLS
handshake.
o TCP Fast Open [RFC7413] can reduce the number of round-trips to
convey DOTS signal.
o While the communication to the DOTS server is quiescent, the DOTS
client may want to probe the server to ensure it has maintained
cryptographic state. Such probes can also keep alive firewall or
NAT bindings. This probing reduces the frequency of needing a new
handshake when a DOTS signal needs to be conveyed to the server.
* A DTLS heartbeat [RFC6520] verifies the server still has DTLS
state by returning a DTLS message. If the server has lost
state, it returns a DTLS Alert. Upon receipt of an un-
authenicated DTLS alert, the DTLS client validates the Alert is
within the replay window (Section 4.1.2.6 of [RFC6347]). It is
difficult for the DTLS client to validate the DTLS alert was
generated by the DTLS server in response to a request or was
generated by an on- or off-path attacker. Thus, upon receipt
of an in-window DTLS Alert, the client SHOULD continue re-
transmitting the DTLS packet (in the event the Alert was
spoofed), and at the same time it SHOULD initiate DTLS session
resumption.
* TLS runs over TCP, so a simple probe is a 0-length TCP packet
(a "window probe"). This verifies the TCP connection is still
working, which is also sufficient to prove the server has
retained TLS state, because if the server loses TLS state it
abandons the TCP connection. If the server has lost state, a
TCP RST is returned immediately.
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5. Protocol for Signal Channel: HTTP REST
A DOTS client can use RESTful APIs discussed in this section to
signal/inform a DOTS server of an attack or any desired IP filtering
rules.
5.1. Mitigation service request
The following APIs define the means to convey an DOTS signal from a
DOTS client to a DOTS server.
5.1.1. Convey DOTS signal
An HTTP POST request will be used to convey DOTS signal to the DOTS
server.
POST {scheme}://{host}:{port}/.well-known/{version}/{URI suffix for DOTS signal}
Accept: application/json
Content-type: application/json
{
"policy-id": number,
"target-ip": string,
"target-port": string,
"target-protocol": string,
}
Figure 2: POST to convey DOTS signal
The header fields are described below.
policy-id: Identifier of the policy represented using a number.
This identifier MUST be unique for each policy bound to the DOTS
client i.e. the policy-id needs to be unique relative to the
active policies with the DOTS server. This identifier must be
generated by the client and used as an opaque value by the server.
This document does not make any assumption about how this
identifier is generated. This is an mandatory attribute.
target-ip: A list of addresses or prefixes under attack. This is an
optional attribute.
target-port: A list of ports under attack. This is an optional
attribute.
target-protocol: A list of protocols under attack. Valid protocol
values include tcp, udp, sctp and dccp. This is an optional
attribute.
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Note: administrative-related clauses may be included as part of the
request (such a contract Identifier or a customer identifier). Those
clauses are out of scope of this document.
The relative order of two rules is determined by comparing their
respective policy identifiers. The rule with lower numeric policy
identifier value has higher precedence (and thus will match before)
than the rule with higher numeric policy identifier value.
To avoid DOTS signal message fragmentation and the consequently
decreased probability of message delivery, DOTS agents MUST ensure
that the DTLS record MUST fit within a single datagram. If the Path
MTU is not known to the DOTS server, an IP MTU of 1280 bytes SHOULD
be assumed. The length of the URL MUST NOT exceed 256 bytes. If UDP
is used to convey the DOTS signal and the request size exceeds the
Path MTU then the DOTS client MUST split the DOTS signal into
separate messages, for example the list of addresses in the target-ip
field could be split into multiple lists and each list conveyed in a
new POST request.
Implementation Note: DOTS choice of message size parameters works
well with IPv6 and with most of today's IPv4 paths. However, with
IPv4, it is harder to absolutely ensure that there is no IP
fragmentation. If IPv4 support on unusual networks is a
consideration and path MTU is unknown, implementations may want to
limit themselves to more conservative IPv4 datagram sizes such as 576
bytes, as per [RFC0791] IP packets up to 576 bytes should never need
to be fragmented, thus sending a maximum of 500 bytes of DOTS signal
over a UDP datagram will generally avoid IP fragmentation.
The following example shows POST request to signal that a Web-Service
is under attack.
POST https://www.example.com/.well-known/v1/DOTS signal
Accept: application/json
Content-type: application/json
{
"policy-id": 123321333242,
"target-ip": {"2002:db8:6401::1", "2002:db8:6401::1"},
"target-port": {"80", "8080", "443"},
"target-protocol": "tcp",
}
Figure 3: POST to signal SOS
The DOTS server indicates the result of processing the POST request
using HTTP response codes. HTTP 2xx codes are success whereas HTTP
4xx codes are some sort of invalid request. If the request is
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missing one or more mandatory attributes then 400 (Bad Request) will
be returned in the response or if the request contains invalid or
unknown parameters then 400 (Invalid query) will be returned in the
response. The HTTP response will include the JSON body received in
the request.
5.1.2. Recall DOTS signal
An HTTP DELETE request will be used to delete an DOTS signal signaled
to the DOTS server. If the DOTS server does not find the policy
number conveyed in the DELETE request in its policy state data then
it responds with 404 HTTP error response code.
DELETE {scheme}://{host}:{port}/.well-known/{URI suffix for DOTS signal}
Accept: application/json
Content-type: application/json
{
"policy-id": number
}
Figure 4: Recall SOS
5.1.3. Retrieving DOTS signal
An HTTP GET request will be used to retrieve an DOTS signal signaled
to the DOTS server. If the DOTS server does not find the policy
number conveyed in the GET request in its policy state data then it
responds with 404 HTTP error response code.
1) To retrieve all DOTS signal signaled by the DOTS client.
GET {scheme}://{host}:{port}/.well-known/{URI suffix for DOTS signal}
2) To retrieve a specific DOTS signal signaled by the DOTS client.
The policy information in the response will be formatted in the same order
it was processed at the DOTS server.
GET {scheme}://{host}:{port}/.well-known/{URI suffix for DOTS signal}
Accept: application/json
Content-type: application/json
{
"policy-id": number
}
Figure 5: GET to retrieve the rules
The following example shows the response of all the active policies
on the DOTS server.
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{
"policy-data": [
{ "policy-id": 123321333242, "target-protocol": "tcp"},
{ "policy-id": 123321333244, "target-protocol": "udp"},
]
}
Figure 6: Response body
5.2. REST
A DOTS client could use HTTPS to provision and manage filters on the
DOTS server. The DOTS client authenticates itself to the DOTS relay,
which in turn authenticates itself to a DOTS server, creating a two-
link chain of transitive authentication between the DOTS client and
the DOTS server. The DOTS relay validates if the DOTS client is
authorized to signal the black-list rules. Likewise, the DOTS server
validates if the DOTS relay is authorized to signal the black-list
rules. To create or purge filters, the DOTS client sends HTTP
requests to the DOTS relay. The DOTS relay acts as an HTTP proxy,
validates the rules and proxies the HTTP requests containing the
black-listed IP addresses to the DOTS server. When the DOTS relay
receives the associated HTTP response from the HTTP server, it
propagates the response back to the DOTS client.
If an attack is detected by the DOTS relay then it can act as a HTTP
client and signal the black-list rules to the DOTS server. Thus the
DOTS relay plays the role of both HTTP client and HTTP proxy.
Network
Resource CPE router Access network
(DOTS client) (DOTS relay) (DOTS server) __________
+-----------+ +----------+ +-------------+ / \
| |____| |_______| |___ | Internet |
|HTTP Client| |HTTP Proxy| | HTTP Server | | |
| | | | | | | |
+-----------+ +----------+ +-------------+ \__________/
Figure 7
JSON [RFC7159] payloads can be used to convey both filtering rules as
well as protocol-specific payload messages that convey request
parameters and response information such as errors.
The figure above explains the protocol with a DOTS relay. The
protocol is equally applicable to scenarios where a DOTS client
directly talks to the DOTS server.
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5.2.1. Filtering Rules
The following APIs define means for a DOTS client to configure
filtering rules on a DOTS server.
5.2.1.1. Install filtering rules
An HTTP POST request will be used to push filtering rules to the DOTS
server.
POST {scheme}://{host}:{port}/.well-known/{version}/{URI suffix for filtering}
Accept: application/json
Content-type: application/json
{
"policy-id": number,
"traffic-protocol": string,
"source-protocol-port": string,
"destination-protocol-port": string,
"destination-ip": string,
"source-ip": string,
"lifetime": number,
"traffic-rate" : number,
}
Figure 8: POST to install filtering rules
The header fields are described below.
policy-id: Identifier of the policy represented using a number.
This identifier MUST be unique for each policy bound to the DOTS
client i.e. the policy-id needs to be unique relative to the
active policies with the DOTS server. This identifier must be
generated by the client and used as an opaque value by the server.
This document does not make any assumption about how this
identifier is generated. This is an mandatory attribute.
traffic-protocol: Valid protocol values include tcp, udp, sctp and
dccp. This is an mandatory attribute.
source-protocol-port: For TCP or UDP or SCTP or DCCP: the source
range of ports (e.g., 1024-65535). This is an optional attribute.
destination-protocol-port: For TCP or UDP or SCTP or DCCP: the
destination range of ports (e.g., 443-443). This information is
useful to avoid disturbing a group of customers when address
sharing is in use [RFC6269]. This is an optional attribute.
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destination-ip: The destination IP addresses or prefixes. This is
an optional attribute.
source-ip: The source IP addresses or prefixes. This is an
optional attribute.
lifetime: Lifetime of the policy in seconds. Indicates the
validity of a rule. Upon the expiry of this lifetime, and if the
request is not reiterated, the rule will be withdrawn at the
upstream network. The request can be reiterated by sending the
same message again. The server always indicates the actual
lifetime in the response. A null value is not allowed. This is
an mandatory attribute.
traffic-rate: This field carries the rate information in IEEE
floating point [IEEE.754.1985] format, units being bytes per
second. A traffic-rate of '0' should result on all traffic for
the particular flow to be discarded. This is an mandatory
attribute.
The relative order of two rules is determined by comparing their
respective policy identifiers. The rule with lower numeric policy
identifier value has higher precedence (and thus will match before)
than the rule with higher numeric policy identifier value.
Note: administrative-related clauses may be included as part of the
request (such a contract Identifier or a customer identifier). Those
clauses are out of scope of this document.
The following example shows POST request to block traffic from
attacker IPv6 prefix 2001:db8:abcd:3f01::/64 to network resource
using IPv6 address 2002:db8:6401::1 to provide HTTPS web service.
POST https://www.example.com/.well-known/v1/filter
Accept: application/json
Content-type: application/json
{
"policy-id": 123321333242,
"traffic-protocol": "tcp",
"source-protocol-port": "1-65535",
"destination-protocol-port": "443",
"destination-ip": "2001:db8:abcd:3f01::/64",
"source-ip": "2002:db8:6401::1",
"lifetime": 1800,
"traffic-rate": 0,
}
Figure 9: POST to install black-list rules
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5.2.1.2. Remove filtering rules
An HTTP DELETE request will be used to delete filtering rules
programmed on the DOTS server.
DELETE {scheme}://{host}:{port}/.well-known/{URI suffix for filtering}
Accept: application/json
Content-type: application/json
{
"policy-id": number
}
Figure 10: DELETE to remove the rules
5.2.1.3. Retrieving installed filtering rules
An HTTP GET request will be used to retrieve filtering rules
programmed on the DOTS server.
1) To retrieve all the black-lists rules programmed by the DOTS client.
GET {scheme}://{host}:{port}/.well-known/{URI suffix for filtering}
2) To retrieve specific black-list rules programmed by the DOTS cient.
GET {scheme}://{host}:{port}/.well-known/{URI suffix for filtering}
Accept: application/json
Content-type: application/json
{
"policy-id": number
}
Figure 11: GET to retrieve the rules
6. IANA Considerations
TODO
7. Security Considerations
Authenticated encryption MUST be used for data confidentiality and
message integrity. (D)TLS based on client certificate MUST be used
for mutual authentication. The interaction between the DOTS agents
requires Datagram Transport Layer Security (DTLS) and Transport Layer
Security (TLS) with a ciphersuite offering confidentiality protection
and the guidance given in [RFC7525] MUST be followed to avoid attacks
on (D)TLS.
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If TCP is used between DOTS agents, attacker will be able to inject
RST packets, bogus application segments, etc., regardless of whether
TLS authentication is used. Because the application data is TLS
protected, this will not result in the application receiving bogus
data, but it will constitute a DoS on the connection. This attack
can be countered by using TCP-AO [RFC5925]. If TCP-AO is used, then
any bogus packets injected by an attacker will be rejected by the
TCP-AO integrity check and therefore will never reach the TLS layer.
Special care should be taken in order to ensure that the activation
of the proposed mechanism won't have an impact on the stability of
the network (including connectivity and services delivered over that
network).
Involved functional elements in the cooperation system must establish
exchange instructions and notification over a secure and
authenticated channel. Adequate filters can be enforced to avoid
that nodes outside a trusted domain can inject request such as
deleting filtering rules. Nevertheless, attacks can be initiated
from within the trusted domain if an entity has been corrupted.
Adequate means to monitor trusted nodes should also be enabled.
8. Acknowledgements
Thanks to C. Jacquenet, Roland Dobbins, Andrew Mortensen, Roman D.
Danyliw for the discussion and comments.
9. References
9.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<http://www.rfc-editor.org/info/rfc2119>.
[RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security
(TLS) Protocol Version 1.2", RFC 5246,
DOI 10.17487/RFC5246, August 2008,
<http://www.rfc-editor.org/info/rfc5246>.
[RFC5925] Touch, J., Mankin, A., and R. Bonica, "The TCP
Authentication Option", RFC 5925, DOI 10.17487/RFC5925,
June 2010, <http://www.rfc-editor.org/info/rfc5925>.
[RFC6347] Rescorla, E. and N. Modadugu, "Datagram Transport Layer
Security Version 1.2", RFC 6347, DOI 10.17487/RFC6347,
January 2012, <http://www.rfc-editor.org/info/rfc6347>.
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[RFC7525] Sheffer, Y., Holz, R., and P. Saint-Andre,
"Recommendations for Secure Use of Transport Layer
Security (TLS) and Datagram Transport Layer Security
(DTLS)", BCP 195, RFC 7525, DOI 10.17487/RFC7525, May
2015, <http://www.rfc-editor.org/info/rfc7525>.
9.2. Informative References
[I-D.ietf-dots-requirements]
Mortensen, A., Moskowitz, R., and T. Reddy, "DDoS Open
Threat Signaling Requirements", draft-ietf-dots-
requirements-00 (work in progress), October 2015.
[I-D.ietf-tls-cached-info]
Santesson, S. and H. Tschofenig, "Transport Layer Security
(TLS) Cached Information Extension", draft-ietf-tls-
cached-info-22 (work in progress), January 2016.
[I-D.ietf-tls-falsestart]
Langley, A., Modadugu, N., and B. Moeller, "Transport
Layer Security (TLS) False Start", draft-ietf-tls-
falsestart-01 (work in progress), November 2015.
[REPORT] "Worldwide Infrastructure Security Report", 2014,
<http://pages.arbornetworks.com/rs/arbor/images/
WISR2014.pdf>.
[RFC0791] Postel, J., "Internet Protocol", STD 5, RFC 791,
DOI 10.17487/RFC0791, September 1981,
<http://www.rfc-editor.org/info/rfc791>.
[RFC4732] Handley, M., Ed., Rescorla, E., Ed., and IAB, "Internet
Denial-of-Service Considerations", RFC 4732,
DOI 10.17487/RFC4732, December 2006,
<http://www.rfc-editor.org/info/rfc4732>.
[RFC5077] Salowey, J., Zhou, H., Eronen, P., and H. Tschofenig,
"Transport Layer Security (TLS) Session Resumption without
Server-Side State", RFC 5077, DOI 10.17487/RFC5077,
January 2008, <http://www.rfc-editor.org/info/rfc5077>.
[RFC5575] Marques, P., Sheth, N., Raszuk, R., Greene, B., Mauch, J.,
and D. McPherson, "Dissemination of Flow Specification
Rules", RFC 5575, DOI 10.17487/RFC5575, August 2009,
<http://www.rfc-editor.org/info/rfc5575>.
Reddy, et al. Expires August 12, 2016 [Page 15]
Internet-Draft Co-operative DDoS Mitigation February 2016
[RFC6269] Ford, M., Ed., Boucadair, M., Durand, A., Levis, P., and
P. Roberts, "Issues with IP Address Sharing", RFC 6269,
DOI 10.17487/RFC6269, June 2011,
<http://www.rfc-editor.org/info/rfc6269>.
[RFC6520] Seggelmann, R., Tuexen, M., and M. Williams, "Transport
Layer Security (TLS) and Datagram Transport Layer Security
(DTLS) Heartbeat Extension", RFC 6520,
DOI 10.17487/RFC6520, February 2012,
<http://www.rfc-editor.org/info/rfc6520>.
[RFC6555] Wing, D. and A. Yourtchenko, "Happy Eyeballs: Success with
Dual-Stack Hosts", RFC 6555, DOI 10.17487/RFC6555, April
2012, <http://www.rfc-editor.org/info/rfc6555>.
[RFC6724] Thaler, D., Ed., Draves, R., Matsumoto, A., and T. Chown,
"Default Address Selection for Internet Protocol Version 6
(IPv6)", RFC 6724, DOI 10.17487/RFC6724, September 2012,
<http://www.rfc-editor.org/info/rfc6724>.
[RFC7159] Bray, T., Ed., "The JavaScript Object Notation (JSON) Data
Interchange Format", RFC 7159, DOI 10.17487/RFC7159, March
2014, <http://www.rfc-editor.org/info/rfc7159>.
[RFC7413] Cheng, Y., Chu, J., Radhakrishnan, S., and A. Jain, "TCP
Fast Open", RFC 7413, DOI 10.17487/RFC7413, December 2014,
<http://www.rfc-editor.org/info/rfc7413>.
Appendix A. BGP
BGP defines a mechanism as described in [RFC5575] that can be used to
automate inter-domain coordination of traffic filtering, such as what
is required in order to mitigate DDoS attacks. However, support for
BGP in an access network does not guarantee that traffic filtering
will always be honored. Since a DOTS client will not receive an
acknowledgment for the filtering request, the DOTS client should
monitor and apply similar rules in its own network in cases where the
DOTS server is unable to enforce the filtering rules. In addition,
enforcement of filtering rules of BGP on Internet routers are usually
governed by the maximum number of data elements the routers can hold
as well as the number of events they are able to process in a given
unit of time.
Authors' Addresses
Reddy, et al. Expires August 12, 2016 [Page 16]
Internet-Draft Co-operative DDoS Mitigation February 2016
Tirumaleswar Reddy
Cisco Systems, Inc.
Cessna Business Park, Varthur Hobli
Sarjapur Marathalli Outer Ring Road
Bangalore, Karnataka 560103
India
Email: tireddy@cisco.com
Dan Wing
Cisco Systems, Inc.
170 West Tasman Drive
San Jose, California 95134
USA
Email: dwing@cisco.com
Prashanth Patil
Cisco Systems, Inc.
Email: praspati@cisco.com
Mike Geller
Cisco Systems, Inc.
3250
Florida 33309
USA
Email: mgeller@cisco.com
Mohamed Boucadair
France Telecom
Rennes 35000
France
Email: mohamed.boucadair@orange.com
Robert Moskowitz
HTT Consulting
Oak Park, MI 42837
United States
Email: rgm@htt-consult.com
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