Electrical computers and digital processing systems: multicomput – Computer-to-computer data addressing
Reexamination Certificate
1999-01-05
2001-03-20
Harrell, Robert B. (Department: 2758)
Electrical computers and digital processing systems: multicomput
Computer-to-computer data addressing
Reexamination Certificate
active
06205489
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to the Internet and, more specifically, the present invention relates to Internet addressing.
2. Background Information
The Internet has brought about an information revolution through the development of computerized information resources, on-line services and the World Wide Web (WWW). With enormous amounts of data on almost any topic imaginable available on the Internet, an ever increasing number of computers and users have been connected to the Internet.
Computers on the Internet address each other with a unique Internet protocol (IP) addresses. Since it is generally easier to memorize words and phrases than it is to remember long sequences of numbers, domain name servers (DNS) perform the important task of converting a host name, such as for example “www.whowhere.com,” to an IP address, such as for example “205.230.1.5.”
FIG. 1
is a block diagram that illustrates a client
101
trying to connect to a web server
103
of an Internet Host ABC. As shown in
FIG. 1
, client
101
makes a DNS resolution request
107
to DNS server
105
to request the IP address of web server
103
. DNS server
105
returns the IP address response
109
in reply to the DNS resolution request
107
. After client
101
has received the IP address response
109
of web server
103
, client
101
sends the hypertext transfer protocol (HTTP) request
111
to web server
103
, which is addressed by IP address included in IP address response
109
, and web server
103
therefore responds with an HTTP response
113
as shown in FIG.
1
.
Although there is a vast number of Internet or WWW sites around the globe, a considerable amount of Internet traffic is served by a small proportion of those sites. As a result, it is desirable for these Internet of WWW sites to have high reliability as well as fast response times. As such, many Internet sites run multiple web servers that serve identical content. By distributing the workload between multiple web servers, an overall site can generally handle more requests than a single web server, each of which has a unique IP address, and the failure of a single web server may not necessarily result in the entire site of an Internet host being down.
FIG. 2
is a block diagram illustrating a client
201
trying to connect to one of the web servers
203
A-C of Internet Host ABC. One approach for client
201
to connect to one of the individual web servers
203
A-C would be for the user or client to remember multiple host names for each of the web servers
203
A-C. To illustrate, web server
203
A could have a host name “www1.Internet_Host_ABC.com,” web server
203
B could have a host name “www2.Internet_Host_ABC.com” and server
203
C could have a host name “www3.Internet_Host_ABC.com.” When a user desires to connect to one of the web servers
203
A-C, the user could use any one of the unique host names. However, since it is undesirable to require a user to memorize different host names for each of the individual web servers of an Internet host, DNS server
205
associates multiple servers, and therefore multiple IP addresses, with a single host name. Thus, when the user, or client
201
makes a DNS resolution request
207
to DNS server
205
for a host name to IP address translation, DNS server
205
returns all IP addresses in IP address response
209
for the host name in random order. In general, client
201
usually uses the first IP address.
In the example illustrated in
FIG. 2
, DNS server
205
returns three IP addresses in IP address response
209
in random order. Each IP address corresponds to one of the web servers
203
A-C. Client
201
uses the first IP address and sends and HTTP request
211
to the web server
203
B identified by the first IP address returned by DNS server
205
. In response, web server
203
B returns an HTTP response
213
back to client
201
.
DNS interactions such as DNS resolution requests
107
and
207
as well as IP address responses
109
and
209
of
FIGS. 1 and 2
respectively constitute a significant portion of total Internet traffic. As a result, some clients
101
or
201
generally cache the Internet host name to IP address translation for a period of time. This concept is sometimes referred to as DNS caching. Several issues are considered when determining the length of time a client should cache an Internet host name to IP address translation. A shorter cache time, sometimes referred to as time-to-live (TTL), leads to increased DNS traffic and slower response times since a client makes a greater number of DNS resolution requests
107
and
207
as shown in
FIGS. 1 and 2
respectively. Longer TTL times may result in a “skewed locking” problem. Skewed locking is generally undesirable and occurs when a disproportionate amount of Internet clients address the same individual web server of an Internet site, even though the Internet site may employ multiple servers.
To illustrate, some of the largest client domains, or Internet service providers (ISPs), together constitute nearly two-thirds of the total Internet traffic. These large client domains cache DNS translations for TTL amount of time. Since existing DNS implementations return IP addresses in random order, as shown in
FIG. 2
, it is possible that all of the major ISPs receive the same sequence of IP addresses for a particular host. Consequently, an undesirable load imbalance results between the multiple web servers of the Internet host. Referring to
FIG. 2
, one web server
203
B may be heavily burdened with HTTP requests
211
while the other web servers
203
A and
203
C remain idle. Consequently, web servers
203
A-C are not efficiently utilized and overall Internet traffic and response times are compromised as a result.
Thus, what is desired is an improved method for providing IP addresses for the multiple web servers of an Internet host. Such a method would efficiently utilize the multiple web servers of an Internet host as well as reduce the skewed locking problems such that overall Internet traffic and response times are reduced.
SUMMARY OF THE INVENTION
A method for providing IP addresses of web servers with a DNS is described. In one embodiment, a DNS is configured to receive a DNS resolution request from a client domain and the DNS returns the IP address of one of the web servers of the Internet host such that the total number of times that the IP address of each particular web server is returned is proportional to the relative weight of each respective web server relative to the total weight of all the web servers of the Internet host. In another embodiment, the top client domains that have recently requested to be connected to the web servers are identified. The number of times each one of the top client domains have requested to be connected to the web servers is also determined. Each of the identified top client domains are then apportioned among the web servers of the Internet host such that the percentage of requests served by each one of the web servers is proportional to the relative weight of each respective web server. A DNS resolution request may then be received from one of the client domains and the DNS then returns the IP address of the web server to which that particular client domain was apportioned. Additional features and benefits of the present invention will become apparent from the detailed description, figures and claims set forth below.
REFERENCES:
patent: 5434974 (1995-07-01), Loucks et al.
patent: 5483652 (1996-01-01), Sudama et al.
patent: 5550984 (1996-08-01), Gelb
patent: 5603029 (1997-02-01), Aman et al.
Padraic Boyle, “Web Site Traffic Cops” http://www.zdnet.com/pcmag/features/loadbal/_open.htm; Feb. 18, 1997.
Greg Yerxa, “Web Server Balancing: An Act Worth Watching” http://techweb.cmp.com
c/814/814ws1.html; Jul. 25, 1997.
Blakely , Sokoloff, Taylor & Zafman LLP
Harrell Robert B.
WhoWhere, Inc.
LandOfFree
Method for providing an internet protocol address with a... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method for providing an internet protocol address with a..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for providing an internet protocol address with a... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2500617