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Versions: 00 01 02 03 04 05 06 07 08 09 RFC 6108

Internet Engineering Task Force                                 C. Chung
Internet-Draft                                               A. Kasyanov
Intended status: Informational                              J. Livingood
Expires: April 11, 2010                                          N. Mody
                                                             B. Van Lieu
                                                                 Comcast
                                                         October 8, 2009


               Example of an ISP Web Notification System
                  draft-livingood-web-notification-00

Status of this Memo

   This Internet-Draft is submitted to IETF in full conformance with the
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Copyright Notice

   Copyright (c) 2009 IETF Trust and the persons identified as the



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   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents in effect on the date of
   publication of this document (http://trustee.ietf.org/license-info).
   Please review these documents carefully, as they describe your rights
   and restrictions with respect to this document.

Abstract

   The objective of this document is to describe one method of providing
   notifications to web browsers being developed by Comcast, a large
   Internet Service Provider (ISP).  Such a notification system can be
   used by an ISP to provide near-immediate notifications to their
   users, such as to warn them that their traffic exhibits patterns that
   are indicative of malware or virus infection, for example.  There are
   many proprietary systems that can perform such notifications on the
   market today, some of which use inline-based Deep Packet Inspection
   (DPI) systems.  This document describes one example of such a system
   that does not rely upon DPI systems, and is instead based in open
   standards and open source systems.  While the system described herein
   is in some ways specific to the DOCSIS networks used by most cable-
   based broadband ISPs, components and concepts described in this
   document can generally be applied to many different types of
   networks.


























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Table of Contents

   1.  Requirements Language  . . . . . . . . . . . . . . . . . . . .  4
   2.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  4
   3.  High-Level Design of the System  . . . . . . . . . . . . . . .  4
   4.  Design Requirements  . . . . . . . . . . . . . . . . . . . . .  5
     4.1.  General  . . . . . . . . . . . . . . . . . . . . . . . . .  5
     4.2.  Web Proxy  . . . . . . . . . . . . . . . . . . . . . . . .  6
     4.3.  ICAP Server  . . . . . . . . . . . . . . . . . . . . . . .  6
     4.4.  Messaging Service  . . . . . . . . . . . . . . . . . . . .  7
   5.  Functional Overview  . . . . . . . . . . . . . . . . . . . . .  7
     5.1.  Functional Components Described  . . . . . . . . . . . . .  7
     5.2.  Functional Diagram . . . . . . . . . . . . . . . . . . . .  9
   6.  High Level Communication Flow  . . . . . . . . . . . . . . . . 10
   7.  Communication Between Web Proxy and ICAP Server  . . . . . . . 11
   8.  End-to-End Web Notification Flow . . . . . . . . . . . . . . . 13
     8.1.  Step-by-Step Description of the End-to-End Web
           Notification Flow  . . . . . . . . . . . . . . . . . . . . 13
     8.2.  Diagram of the End-to-End Web Notification Flow  . . . . . 14
   9.  Example HTTP Headers for a Web Notification  . . . . . . . . . 16
   10. Deployment Considerations  . . . . . . . . . . . . . . . . . . 17
   11. Security Considerations  . . . . . . . . . . . . . . . . . . . 17
   12. IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 18
   13. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 18
   14. References . . . . . . . . . . . . . . . . . . . . . . . . . . 18
     14.1. Normative References . . . . . . . . . . . . . . . . . . . 18
     14.2. Informative References . . . . . . . . . . . . . . . . . . 19
   Appendix A.  Document Change Log . . . . . . . . . . . . . . . . . 20
   Appendix B.  Open Issues . . . . . . . . . . . . . . . . . . . . . 20
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 20





















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1.  Requirements Language

   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 [RFC2119].


2.  Introduction

   Internet Service Providers (ISPs) have a need for a system that is
   capable of communicating with selected customers in a nearly
   immediate manner.  Given the prevalence of the web browser as the
   predominant client software in use by Internet users, the web browser
   is an ideal vehicle for providing notifications.  This document
   describes a system being developed by Comcast, a large broadband ISP,
   to provide notifications to web browsers, which can be used to
   provide such near-immediate notifications to users.  This type of
   system is designed to provide a non-intrusive, though obvious,
   notification to a user's web browser.

   In evaluating potential solutions, most commercially available
   systems were either proprietary and/or required inline-based Deep
   Packet Inspection (DPI) systems.  However, Comcast and many other
   ISPs may desire to use a system based on open standards, non-
   proprietary software, and which does not require the use of DPI.
   While the system described herein is specific to the Data-Over-Cable
   Service Interface Specifications (DOCSIS, [CableLabs DOCSIS])
   networks used by most cable-based broadband ISPs, components and
   concepts described in this document can generally be applied to many
   different types of networks.


3.  High-Level Design of the System

   The web notification system design is based on the use of the
   Internet Content Adaptation Protocol [RFC3507].  The design uses open
   source applications such as the Squid Web Proxy, the GreasySpoon ICAP
   server, and Apache Tomcat.  The ICAP protocol allows for message
   transformation or adaptation.  An ICAP client passes a HyperText
   Transport Protocol (HTTP, [RFC2616]) message to an ICAP server for
   some type of processing.  The ICAP Server will in turn respond back
   to the client with the modified HTTP message containing the
   notification message.

   Message modification itself may then be provided via either a HTTP
   request or HTTP response.  However, for the specific system described
   in this document, only the HTTP response is modified, by using the
   'respmod' method defined in Section 3.2 of [RFC3507].



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4.  Design Requirements

   This section describes all of the requirements taken into
   consideration for the design of this system.

4.1.  General

   REQ1:   TCP Port 80: The system should provide notifications via TCP
           port 80, the well-known port for HTTP traffic.

   REQ2:   Whitelisting: It is possible that the HyperText Markup
           Language (HTML, [RFC1866]) or JavaScript used for
           notifications may cause problems for access to a particular
           website.  Therefore, such a system should be capable of using
           a whitelist of website Uniform Resource Indicators (URIs,
           [RFC2396]) or Fully Qualified Domain Named (FQDNs, Section
           5.1 of [RFC1035]) that conflict with the system, to instruct
           the system to not provide a notifications related to certain
           sites, in order to reduce any errors or unexpected results.

   REQ3:   Instant Messaging (IM): Some IM clients use TCP port 80 in
           their communications, often as an alternate port when
           standard, well-known ports do not work.  This system should
           not conflict with or cause unexpected results for IM clients.

   REQ4:   Handling of Active Sessions: To the extent that a web
           notification system must temporarily route TCP port 80
           traffic, in order to provide a notification, previously
           active TCP port 80 sessions should be maintained.

   REQ5:   No TCP Resets: The use of TCP resets has been widely
           criticized, both in the Internet community generally as well
           as in [RFC3360].  As such, except for the case of
           unintentional errors, the use of TCP resets must not be used.

   REQ6:   Non-Disruptive: The web notification system should not
           disrupt the end user experience, such as causing significant
           clients errors.

   REQ7:   Notification Acknowledgement: Once a user responds and
           acknowledges a notification, the notification should
           immediately stop, so it is not repeatedly and annoyingly
           presented, again and again, in a short period of time.

   REQ8:   Non-Modification of Content: Such a system should not
           significantly alter the content of any website the user is
           accessing.




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   REQ9:   Unexpected Content: The system should transparently handle
           traffic for which it cannot provide a web notification.
           Thus, widely varying content should be expected, and all such
           unexpected traffic should be able to be handled by the system
           without generating errors or unexpected results.

   REQ10:  No Caching: Web content must not be cached by the system.

   REQ11:  No Advertising Replacement or Insertion: The system must not
           be used to replace any advertising provided by a website, or
           insert advertising into websites where none was intended by
           the owner of a given website.

4.2.  Web Proxy

   REQ12:  Open-Source Software: The system should use an open source
           web proxy server, such as Squid.  (While it is possible to
           use any web proxy, the use of open source, and openly
           documented software is recommended.)

   REQ13:  ICAP Client: The web proxy server should have an integrated
           ICAP client.

   REQ14:  Access Control: Access to the proxy should be limited
           exclusively to the IP addresses of users for which
           notifications are intended, and only for limited periods of
           time.  Furthermore, if a Session Management Broker (SMB) is
           utilized, as described in Section 5.1 below, then the proxy
           should restrict access only to the IP of the SMB.

4.3.  ICAP Server

   REQ15:  Request and Response Support: The system should support both
           request and response adaptation.

   REQ16:  Consistency: The system must be able to consistently provide
           a specific notification.

   REQ17:  Multiple Notification Types: The system must be able to
           provide many different types of notifications.

   REQ18:  Simultaneous Differing Notifications: The system must be able
           to simultaneously serve multiple notifications, including
           notifications of varying types, to different users.  As a
           result, User A should be able to get the notification
           intended specifically for User A, at the same time that User
           B receives an entirely different notification, which was
           intended specifically for User B.



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4.4.  Messaging Service

   REQ19:  Messaging Service: The Messaging Service, as described in
           Section 5.1 below caches the notifications for each specific
           user.  Thus, by caching the notification messages, the system
           may provide notifications without significantly affecting the
           web browsing experience of the user.

   REQ20:  Process Acknowledgements: The Messaging Service should
           process acknowledgements to properly remove entries from the
           cache and forward acknowledgements to the Messaging Service.

   REQ21:  Ensure Notification Targeting Accuracy: The Messaging Service
           must ensure that notifications are presented to the intended
           users.

   REQ22:  Keep Records for Customer Care: The Messaging Service should
           maintain some type of record that a notification has been
           presented and/or acknowledged, in case a user inquires with
           customer care personnel.


5.  Functional Overview

   This section defines the various core functional components of the
   system.  These components are then shown in a diagram to describe how
   the various components are linked and relate to one another.

5.1.  Functional Components Described

   It should be noted that when specific software cited is but one
   example of a possible selection for each component.  As the state of
   the art changes, so too many the best or most appropriate software
   choices here vary.

   5.1.A.  Web Proxy: A standard web proxy server.  The initial version
           of this system uses the Squid Proxy, an open source
           application in wide use.

   5.1.B.  ICAP Server: This should be an open source application
           capable of supporting content adaptation in both request and
           response modes.  The ICAP Server retrieves the notifications
           from the Messaging service cache when content adaption is
           needed.  The initial version of this system uses GreasySpoon,
           an open source application.






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   5.1.C.  Customer Database: The Customer Database holds the user
           information including the notifications setup for each user.
           The database may also hold status of which users were
           notified and users pending notification.

   5.1.D.  The Messaging Service is a process engine that retrieves
           specific web notification messages from a catalog of possible
           notifications.  A When a notification for a specific user is
           not in cache, the process retrieves this information from the
           Customer Database and populates the cache for a specific
           period of time.  The initial version of this service uses
           Apache Tomcat, an open source application.

   5.1.E.  Session Management Broker: A Load Balancer (LB) with a
           customized layer 7 inspection policy was used to
           differentiate between HTTP and non-HTTP traffic on TCP port
           80.  The LB functions as a full stateful TCP proxy with the
           ability to forward packets from existing TCP sessions that do
           not exist in the internal session table.  New HTTP sessions
           are load balanced to a proxy layer either transparently or
           using source Network Address Translation (NAT [RFC1631]) from
           the LB, with additional layer 7 inspection as needed.
           Established TCP sessions not in the LB session table are
           simply forwarded to the destination transparently via the
           proxy layer.  The initial version of this system uses a
           Session Management Broker which has been developed internally
           by Comcast.
























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5.2.  Functional Diagram


   +--------+        +------------+        +----------+
   |  ICAP  | <----> | Messaging  | <----> | Customer |
   | Server |        |  Service   |        | Database |
   +--------+        +------------+        +----------+
     ^
     |                +----------+
     |                |          |
     |      +-------> | Internet | <-------+
     |      |         |          |         |
     |      |         +----------+         |
     |      |              ^               |
     |      |              |               |
     v      v              |               |
   +----------+            V               v
   |+--------+|        +-------+       +--------+
   ||  ICAP  || <----> |  SMB  | <---> | Access |
   || Client ||        +-------+       | Router |
   |+--------+|                        +--------+
   || SQUID  ||                            ^
   || Proxy  ||                            |
   |+--------+|                            |
   +----------+                            |
                                           v
                                     +----------+
                                     | Network  |
                                     | Element* |
                                     +----------+
                                          ^
                                          |
                                          |
                                          v
                                       +------+
                                       |  PC  |
                                       +------+

   * An access network element, such as a Cable Modem Termination
     System (CMTS).



         Figure 1: Web Notification System - Functional Components







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6.  High Level Communication Flow

   6.A.  Setup Differentiated Services (DiffServ): Using DiffServe
         [RFC2474] [RFC2475] [RFC2597] [RFC3140] [RFC3246] [RFC3260]
         [RFC4594], set a policy to direct TCP port 80 traffic to the
         web notification system's web proxy.

   6.B.  Session Management: TCP port 80 Packets are routed to a load
         balancer where the load balancer then distinguishes new TCP
         port 80 sessions as HTTP or non-HTTP.  For HTTP sessions, the
         load balancer forwards to the proxy.  For non-HTTP traffic such
         as instant messaging (IM), the load balancer either forwards to
         a TCP proxy layer for handling or operates as a full TCP proxy
         for non-HTTP sessions and forwards to the destination.  Pre-
         established TCP sessions on port 80 are identified by the load
         balancer and forwarded with no impact.

   6.C.  Web Proxy Forwards Request: The web proxy forwards the HTTP
         request on to the destination site, as a web proxy normally
         would do.

   6.D.  On Response, Send Message to ICAP Server: When the HTTP
         response is received, the web proxy sends a message to the ICAP
         server for the web notification.

   6.E.  Messaging Service: Messaging Service should respond with
         appropriate notification content or null response if
         notification is not cached.

   6.F.  ICAP Server Responds: The ICAP server responds and furnishes
         the appropriate content of the appropriate web notification to
         the web proxy.

   6.G.  Web Proxy Sends Response: The web proxy then sends a "200 OK"
         HTTP message to the original web client, containing the
         originally requested content and the web notification.

   6.H.  User Response: The user observes the web notification, and
         clicks an appropriate option, such as: OK/acknowledged, snooze/
         remind me later, etc.

   6.I.  More Information: Depending upon the notification, the user may
         be provided with more information.  Using the example of a web
         notification to a user explaining that it is highly likely that
         they have been infected with a virus or malware, the user may
         click an acknowledgement that indicates that clicking that will
         take them to a page with information about virus/malware
         scanning and remediation.



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   6.J.  Turn Down DiffServ: Once the notification transaction has
         completed, remove any special DiffServ settings.


7.  Communication Between Web Proxy and ICAP Server














































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   +------------+
   |            |
   |  www URL   |
   |            |
   +------------+
      ^      |
      |      |
   (2)|      |(3)
      |      |
      |      v
     +--------+     (4)     +--------+     (4)     +--------+
     |        |------------>|        |------------>|        |
     |        |             |        |             |        |
     |        |     (5)     |        |     (5)     |        |
     |        |<------------|        |<------------|        |
     | Proxy  |             |  ICAP  |             |  ICAP  |
     | Module |     (6)     | Client |     (6)     | Server |
     |        |------------>|        |------------>|        |
     |        |             |        |             |        |
     |        |     (7)     |        |     (7)     |        |
     |        |<------------|        |<------------|        |
     +--------+             +--------+             +--------+
      ^      |
      |      |
   (1)|      |(8)
      |      |
      |      v
   +------------+              (9)             +------------+
   |            |----------------------------->|            |
   |            |                              |            |
   |  Browser   |                              | Web Server |
   |            |              (10)            |            |
   |            |<-----------------------------|            |
   +------------+                              +------------+


   (1) - HTTP GET (TCP 80)
   (2) - Proxy HTTP GET (TCP 80)
   (3) - HTTP 200 OK w/ Response
   (4) - ICAP RESPMOD
   (5) - ICAP 200 OK
   (6) - TCP Stream - Encapsulate Header
   (7) - ICAP 200 OK Insert Message
   (8) - HTTP 200 OK w/ Response + Message Frame
   (9) - HTTP GET for Message
   (10) - HTTP 200 w/ Message Content





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         Figure 2: Communication Between Web Proxy and ICAP Server


8.  End-to-End Web Notification Flow

8.1.  Step-by-Step Description of the End-to-End Web Notification Flow

   Policy Based Routing

   1.  TCP port 80 packets from the users that need to be notified maybe
       routed to the web proxy via policy based routing.

   2.  Packets are forwarded to the Load Balancer, which establishes a
       session with the web proxy and routes the packets to the proxy.

   Web Proxy

   1.  User's HTTP request is directed to the web proxy.

   2.  Web proxy received HTTP traffic and retrieves content from the
       requested web site.

   3.  Web proxy receives response and forwards it to the ICAP server
       for response adaptation.

   4.  The ICAP Server checks the HTTP content in order to determine
       whether notification message can be inserted.

   5.  The ICAP Server initiates a HTTP Post to the Messaging Service
       cache process with the IP address of the user.

   6.  If a notification message for the user exists then the
       appropriate notification is cached on the Messaging Service.  The
       Messaging Service then returns the appropriate HTML content to
       the ICAP Server.

   7.

       A.  Once the notification message is retrieved from Messaging
           Service cache the ICAP server may insert the notification
           message in the HTTP response body without altering or
           modifying the original content of the HTTP 200 OK response.

       B.  The ICAP Server then sends the response back to the web
           proxy, which in turn forwards the HTTP 200 OK response back
           to the browser.





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   8.  If the user IP is not found or provisioned for a notification
       message, then the ICAP Server should return a '204 No
       modifications needed' response to the ICAP Client as defined in
       section 4.3.3 of [RFC3507].  As a result, the user will not
       receive any web notification message.

   9.  The user observes the web notification, and clicks an appropriate
       option, such as: OK/acknowledged, snooze/ remind me later, etc.

8.2.  Diagram of the End-to-End Web Notification Flow

   This flow shows the communications flow from the web client, through
   the entire system.






































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                      ICAP     ICAP    Message          Customer
   Browser   Proxy   Client   Server   Service  Internet   DB
     |  HTTP  |         |         |        |        |        |
     |  GET   |         | Proxy   |        |        |        |
     +------->|         | Request |        |        |        |
     |        +---------|---------|--------|------->|        |
     |        |         |         | 200 OK |        |        |
     |        |<--------|---------|--------|--------+        |
     |        | ICAP    |         |        |        |        |
     |        | RESPMOD | ICAP    |        |        |        |
     |        +-------->| RESPMOD |        |        |        |
     |        |         +-------->|        |        |        |
     |        |         |         | Check  |        |        |
     |        |         |         | Cache  |        |        |
     |        |         |         | for IP |        | Cache  |
     |        |         |         | Match  |        | Miss   |
     |        |         |         +------->|        | Request|
     |        |         |         |        |        | Type   |
     |        |         |         |        +--------|------->|
     |        |         | Cache   |        |        |        |
     |        |         | Miss    |        |        |        |
     |        |         | No      |        |        |        |
     |        |         | Insert  |        |        |        |
     |        |<--------|---------|--------+        |Type    |
     | 200 OK |         |         |        |        |Returned|
     | No     |         |         |        |<-------|--------+
     | Insert |         |         |        |        |        |
     |<-------+         |         |        |        |        |
     |        |         | Cache   |        |        |        |
     |        |         | Hit     |        |        |        |
     |        |         | Insert  |        |        |        |
     | 200 OK |<--------|---------|--------+        |        |
     | Insert |         |         |        |        |        |
     |<-------+         |         |        |        |        |
     |        |         | HTTP    |        |        |        |
     |        |         | GET to  |        |        |        |
     |        |         | Content |        |        |        |
     |        |         | Portal  |        |        |        |
     +--------|---------|---------|--------|------->|        |
     |        |         | 200 OK  |        |        |        |
     |        |         | w/      |        |        |        |
     |        |         | Notify  |        |        |        |
     |<-------|---------|---------|--------|--------+        |
     |        |         |         |        |        |        |


                Figure 3: End-to-End Web Notification Flow




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9.  Example HTTP Headers for a Web Notification


Web-Browser HTTP Headers

----------------------------------------------
1.  HTTP Get Request to www.example.com
----------------------------------------------

http://www.example.com/

GET / HTTP/1.1
Host: www.example.com
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.14)
        Gecko/20080404 Firefox/2.0.0.14
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: en-us,en;q=0.5
Accept-Encoding: gzip,deflate
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7
Keep-Alive: 300
Connection: keep-alive
Pragma: no-cache

----------------------------------------------
2.  Response from www.example.com via PROXY
----------------------------------------------

HTTP/1.x 200 OK
Date: Thu, 08 May 2008 16:26:29 GMT
Server: Apache/2.2.3 (CentOS)
Last-Modified: Tue, 15 Nov 2005 13:24:10 GMT
Etag: "b80f4-1b6-80bfd280"
Accept-Ranges: bytes
Content-Length: 438
Connection: close
Content-Type: text/html; charset=UTF-8
Age: 18
X-Cache: HIT from localhost.localdomain
Via: 1.0 localhost.localdomain (squid/3.0.STABLE5)
Proxy-Connection: keep-alive

-----------------------------------------------------------
3.  Example of JavaScript containing Notification Insertion
-----------------------------------------------------------

<!--all elements used in a notification should have css properties
defined to avoid unwanted inheritance from parent page-->
<style type="text/css">



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Internet-Draft  Example of an ISP Web Notification System   October 2009


#example {
  position: absolute; left: 100px; top: 50px;
  z-index: 9999999; height: auto; width: 550px;
  padding: 10px;
  border: solid 2px black;
  background-color:#FDD017;
  opacity: 0.8; filter: alpha(opacity = 80);
}
</style>

<script language="javascript" type="text/javascript">
// ensure that content is not part of an iframe
if (self.location == top.location) {
  // this is a floating div with 80% transparency
  document.write('<div id="example" name="example">');
  document.write('<h2>IMPORTANT MESSAGE</h2>');
  document.write('<p>Lorem ipsum dolor sit amet, consecteteur ');
  document.write('adipisicing elit, sed do eiusmod tempor ');
  document.write('incididunt ut labore et dolore magna aliqua. ');
  document.write('Ut enim ad minim veniam, quis nostrud ');
  document.write('exercitation ullamco laboris nisi ut aliquip ex ');
  document.write('ea commodo consequat.');
  document.write('</div>');
}</script>

----------------------------------------------


                                 Figure 4


10.  Deployment Considerations

   The components of such a web notification system should be
   distributed throughout a network, close to users.  When distributed
   in such a manner, this ensures that performance remains acceptable
   across a wide geography.  It is also a best practice that a HTTP-
   aware load balancer is used in each datacenter where servers are
   located, so that traffic can be spread across N+1 servers and the
   system can be easily scaled out.


11.  Security Considerations

   There are no security considerations have yet been added document.
   Will be a focus of a future update.





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Internet-Draft  Example of an ISP Web Notification System   October 2009


12.  IANA Considerations

   There are no IANA considerations in this document.

   NOTE TO RFC EDITOR: PLEASE REMOVE THIS NULL SECTION PRIOR TO
   PUBLICATION.


13.  Acknowledgements

   The authors will probably wish to acknowledge someone's review or
   contribution at some point, which is the purpose of this section. :-)


14.  References

14.1.  Normative References

   [RFC1035]  Mockapetris, P., "Domain names - implementation and
              specification", STD 13, RFC 1035, November 1987.

   [RFC1631]  Egevang, K. and P. Francis, "The IP Network Address
              Translator (NAT)", RFC 1631, May 1994.

   [RFC1866]  Berners-Lee, T. and D. Connolly, "Hypertext Markup
              Language - 2.0", RFC 1866, November 1995.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC2396]  Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
              Resource Identifiers (URI): Generic Syntax", RFC 2396,
              August 1998.

   [RFC2434]  Narten, T. and H. Alvestrand, "Guidelines for Writing an
              IANA Considerations Section in RFCs", BCP 26, RFC 2434,
              October 1998.

   [RFC2474]  Nichols, K., Blake, S., Baker, F., and D. Black,
              "Definition of the Differentiated Services Field (DS
              Field) in the IPv4 and IPv6 Headers", RFC 2474,
              December 1998.

   [RFC2475]  Blake, S., Black, D., Carlson, M., Davies, E., Wang, Z.,
              and W. Weiss, "An Architecture for Differentiated
              Services", RFC 2475, December 1998.

   [RFC2597]  Heinanen, J., Baker, F., Weiss, W., and J. Wroclawski,



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Internet-Draft  Example of an ISP Web Notification System   October 2009


              "Assured Forwarding PHB Group", RFC 2597, June 1999.

   [RFC2616]  Fielding, R., Gettys, J., Mogul, J., Frystyk, H.,
              Masinter, L., Leach, P., and T. Berners-Lee, "Hypertext
              Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999.

   [RFC2782]  Gulbrandsen, A., Vixie, P., and L. Esibov, "A DNS RR for
              specifying the location of services (DNS SRV)", RFC 2782,
              February 2000.

   [RFC2915]  Mealling, M. and R. Daniel, "The Naming Authority Pointer
              (NAPTR) DNS Resource Record", RFC 2915, September 2000.

   [RFC3140]  Black, D., Brim, S., Carpenter, B., and F. Le Faucheur,
              "Per Hop Behavior Identification Codes", RFC 3140,
              June 2001.

   [RFC3246]  Davie, B., Charny, A., Bennet, J., Benson, K., Le Boudec,
              J., Courtney, W., Davari, S., Firoiu, V., and D.
              Stiliadis, "An Expedited Forwarding PHB (Per-Hop
              Behavior)", RFC 3246, March 2002.

   [RFC3260]  Grossman, D., "New Terminology and Clarifications for
              Diffserv", RFC 3260, April 2002.

   [RFC3261]  Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston,
              A., Peterson, J., Sparks, R., Handley, M., and E.
              Schooler, "SIP: Session Initiation Protocol", RFC 3261,
              June 2002.

   [RFC3263]  Rosenberg, J. and H. Schulzrinne, "Session Initiation
              Protocol (SIP): Locating SIP Servers", RFC 3263,
              June 2002.

   [RFC3507]  Elson, J. and A. Cerpa, "Internet Content Adaptation
              Protocol (ICAP)", RFC 3507, April 2003.

   [RFC4594]  Babiarz, J., Chan, K., and F. Baker, "Configuration
              Guidelines for DiffServ Service Classes", RFC 4594,
              August 2006.

14.2.  Informative References

   [CableLabs DOCSIS]
              CableLabs, "Data-Over-Cable Service Interface
              Specifications", CableLabs Specifications Various DOCSIS
              Reference Documents, <http://www.cablelabs.com/
              specifications/archives/docsis.html>.



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   [RFC3360]  Floyd, S., "Inappropriate TCP Resets Considered Harmful",
              BCP 60, RFC 3360, August 2002.


Appendix A.  Document Change Log

   [RFC Editor: This section is to be removed before publication]

   -00 version:

   o  -00 published


Appendix B.  Open Issues

   1 - Abstract: change "being developed by Comcast" to "used by
   Comcast" depending upon status of field testing

   2 - Intro: change "system being developed by Comcast" to "system used
   by Comcast" depending upon status of field testing

   3 - Need an RFC reference for JavaScript, upon first use?

   4 - Add an informative reference to
   draft-oreirdan-mody-bot-remediation-03

   5 - Add content to Security Considerations


Authors' Addresses

   Chae Chung
   Comcast Cable Communications
   One Comcast Center
   1701 John F. Kennedy Boulevard
   Philadelphia, PA  19103
   US

   Email: chae_chung@cable.comcast.com
   URI:   http://www.comcast.com











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Internet-Draft  Example of an ISP Web Notification System   October 2009


   Alex Kasyanov
   Comcast Cable Communications
   One Comcast Center
   1701 John F. Kennedy Boulevard
   Philadelphia, PA  19103
   US

   Email: alexander_kasyanov@cable.comcast.com
   URI:   http://www.comcast.com


   Jason Livingood
   Comcast Cable Communications
   One Comcast Center
   1701 John F. Kennedy Boulevard
   Philadelphia, PA  19103
   US

   Email: jason_livingood@cable.comcast.com
   URI:   http://www.comcast.com


   Nirmal Mody
   Comcast Cable Communications
   One Comcast Center
   1701 John F. Kennedy Boulevard
   Philadelphia, PA  19103
   US

   Email: nirmal_mody@cable.comcast.com
   URI:   http://www.comcast.com


   Brian Van Lieu
   Comcast Cable Communications
   One Comcast Center
   1701 John F. Kennedy Boulevard
   Philadelphia, PA  19103
   US

   Email: brian_vanlieu@cable.comcast.com
   URI:   http://www.comcast.com









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Html markup produced by rfcmarkup 1.118, available from https://tools.ietf.org/tools/rfcmarkup/