2. URL (Uniform Resource
Locator)
URL (Uniform Resource Locator) is often defined
as a string of characters that is directed to an
address. It is a very commonly used way to locate
resources on the web. It provides a way to
retrieve the presentation of the physical location
by describing its network location or primary
access mechanism
. The protocol is described within the URL which
is employed to retrieve the resource and resource
name. The URL contains http/https at the start if
the resource may be a web type resource.
Similarly, it begins with ftp if the resource may be
a file and mailto if the resource is an email
address
3. URI (Uniform Resource
Identifier):
Similar to URL, URI (Uniform Resource Identifier)
is also a string of characters that identifies a
resource on the web either by using location,
name or both. It allows uniform identification of
the resources.
Such identification enables interaction with
representations of the resource over a network,
typically the World Wide Web, using
specific protocols. Schemes specifying a
concrete syntax and associated protocols define
each URI. The most common form of URI is the
Uniform Resource Locator (URL), frequently
referred to informally as a web address.
4. URL URI
URL is used to describe the identity
of an item.
URI provides a technique for defining
the identity of an item.
URL links a web page, a component
of a web page or a program on a
web page with the help of accessing
methods like protocols.
URI is used to distinguish one
resource from other regardless of the
method used.
URL provides the details about what
type of protocol is to be used.
URI doesn’t contains the protocol
specification.
URL is a type of URI. URI is the superset of URL.
5. URI Syntax
The generic form of any URI
is scheme:[//[user:password@]host[:port]][/]path[?query][#fragment]
Scheme: The scheme lays out the concrete syntax and
any associated protocols for the URI. Schemes are case-
insensitive and are followed by a colon. Ideally, URI
schemes should be registered with the Internet Assigned
Numbers Authority (IANA), although nonregistered
schemes can also be used.While the two slashes shown in
the example above are required by some schemes, they
are not required by all schemes, including authority
components, which are described below.
6. Authority component: An authority component is made
up of multiple parts: an optional authentication section, a
host -- consisting of either a registered name or an IP
address -- and an optional port number. The authentication
section contains the username and password, which are
separated by a colon and followed by the symbol for at
(@). After the @ comes the hostname, which is in turn
followed by a colon and then a port number. It is important
to note that IPv4 addresses must be in dot-decimal
notation, and IPv6 addresses must be enclosed in
brackets.
The path, which contains data, is notated by a sequence
of segments separated by slashes. The path must begin
with a single slash if an authority part was present. It may
also begin with a single slash even if there is no authority
part, but it cannot begin with a double slash. Keep in mind
that while this part of the syntax may closely resemble a
particular file path, it does not always imply a relation to
that file system path.
7. Query (optional): The query contains a string of
nonhierarchical data. Although the syntax is not well-
defined, it is most often a sequence of attribute value
pairs separated by a delimiter, such as an ampersand
or a semicolon. The query is separated from the
preceding part by a question mark.
Fragment (optional): The fragment contains a
fragment identifier that provides direction to a
secondary resource. For example, if the primary
resource is an HTML document, the fragment is often
an ID attribute of a specific element of that document.
If the fragment identifies a certain section of an article
identified by the rest of the URI, a Web browser will
scroll this particular element into view. The fragment
is separated from the preceding part by a hash (#).
8. scheme component followed by a colon (:), consisting of a sequence of characters beginning
with a letter and followed by any combination of letters, digits, plus (+), period (.), or hyphen
(-). Although schemes are case-insensitive, the canonical form is lowercase and documents
that specify schemes must do so with lowercase letters. Examples of popular schemes
include http, https, ftp, mailto, file, data,. URI schemes should be registered with the Internet
Assigned Numbers Authority (IANA), although non-registered schemes are used in practice
userinfo subcomponent that may consist of a user name and an
optional password preceded by a colon (:), followed by an at symbol (@)
host subcomponent, consisting of either a registered name (including but not limited to
a hostname), or an IP address
path component, consisting of a sequence of path segments separated by a slash (/).
query component preceded by a question mark (?), containing a query string of non-
hierarchical data.
fragment component preceded by a hash (#). The fragment contains a fragment
identifier providing direction to a secondary resource, such as a section heading in an article
identified by the remainder of the URI
9. These URIs are frequently referred to as URLs,. The schemes
covered are:
http: Hypertext Transfer Protocol
ftp: File Transfer protocol
Gopher: Gopher protocol
mailto : Electronic mail address
News: Usenet newst
Telnet , rlogin and tn3270: Reference to interactive sessions
wais: Wide Area Information Servers
File: Local file accessThe following schemes are proposed as
essential to the unification of the web with electronic mail, but
not currently (to the author's knowledge) implemented:
Mid: Message identifiers for electronic mail
cid : Content identifiers for MIME body part
10. XMPP
XMPP is the Extensible Messaging and Presence
Protocol, a set of open technologies for instant
messaging, presence, multi-party chat, voice and
video calls, collaboration, lightweight middleware,
content syndication, and generalized routing of XML
data.
XMPP was originally developed in the Jabber open-
source community to provide an open, decentralized
alternative to the closed instant messaging services
at that time. XMPP offers several key advantages
over such services:
11. Extensible Messaging and Presence
Protocol (XMPP) is a communication
protocol for message-oriented middleware based
on XML (Extensible Markup Language).It enables
the near-real-time exchange of structured
yet extensible data between any two or more
network entities.Originally named Jabber, the
protocol was developed by the eponymous open-
source community in 1999 for near real-time instant
messaging (IM), presence information, and contact
list maintenance. Designed to be extensible, the
protocol has been used also for publish-subscribe
systems, signalling for VoIP, video, file
transfer, gaming, the Internet of Things (IoT)
applications such as the smart grid, and social
networking services.
12. Open — the XMPP protocols are free, open, public, and easily understandable; in
addition, multiple implementations exist in the form clients, servers, server components,
and code libraries.
Standard — the Internet Engineering Task Force (IETF) has formalized the core XML
streaming protocols as an approved instant messaging and presence technology. The
XMPP specifications were published as RFC 3920 and RFC 3921 in 2004, and
the XMPP Standards Foundation continues to publish many XMPP Extension
Protocols. In 2011 the core RFCs were revised, resulting in the most up-to-date
specifications (RFC 6120, RFC 6121, and RFC 7622).
Proven — the first Jabber/XMPP technologies were developed by Jeremie Miller in
1998 and are now quite stable; hundreds of developers are working on these
technologies, there are tens of thousands of XMPP servers running on the Internet
today, and millions of people use XMPP for instant messaging through public services
such as Google Talk and XMPP deployments at organizations worldwide.
Decentralized — the architecture of the XMPP network is similar to email; as a result,
anyone can run their own XMPP server, enabling individuals and organizations to take
control of their communications experience.
Secure — any XMPP server may be isolated from the public network (e.g., on a
company intranet) and robust security using SASL and TLS has been built into the
core XMPP specifications. In addition, the XMPP developer community is actively
working on end-to-end encryption to raise the security bar even further.
Extensible — using the power of XML, anyone can build custom functionality on top of
the core protocols; to maintain interoperability, common extensions are published in
the XEP series, but such publication is not required and organizations can maintain
their own private extensions if so desired.
Flexible — XMPP applications beyond IM include network management, content
syndication, collaboration tools, file sharing, gaming, remote systems monitoring, web
services, lightweight middleware, cloud computing, and much more.
Diverse — a wide range of companies and open-source projects use XMPP to build
and deploy real-time applications and services; you will never get “locked in” when you
use XMPP technologies.
13. XMPP features such as federation across
domains, publish/subscribe, authentication and its
security even for mobile endpoints are being used
to implement the Internet of Things. Several
XMPP extensions are part of the experimental
implementation: Efficient XML Interchange (EXI)
Format; Sensor Data;Provisioning;Control
14. RFID Technology and Its Applications in Internet of
Things (IOT)
Radio frequency identification system (RFID) is an
automatic technology and aids machines or
computers to identify objects, record metadata or
control individual target through radio waves .The
RFID technology was first appeared in 1945, as an
espionage tool for the Soviet Union, which
retransmitted incident radio waves with audio
15. A typically RFID system is consisted of tags
(transmitters/ responders) and readers
(transmitters/receivers) . The tag is a microchip
connected with an antenna, which can be attached to
an object as the identifier of the object. The RFID
reader communicates with the RFID tag using radio
waves. The main advantage of RFID technology is the
automated identification and data capture that
promises wholesale changes across a broad
spectrum of business activities and aims to reduce the
cost of the already used systems such as bar codes.
16. RFID System
RFID systems are composed of three main components: RFID tags,
reader, application system:
RFID tags: also known as transponders (transmitter/ responder), are
attached to the objects to count or identify. Tags could be either active
or passive. Active tags are those that have partly or fully battery
powered, have the capability to communicate with other tags, and can
initiate a dialogue of their own with the tag reader. Passive tags, on the
other hand, do not need any internal power source but are powered up
by the tag reader. Tags consist mainly of a coiled antenna and a
microchip, with the main purpose of storing data.
17. Reader: also known as transceiver (transmitter/receiver)
made up of a radio frequency interface (RFI) module and
control unit. Its main functions are to activate the tags,
structure the communication sequence with the tag, and
transfer data between the application software and tags.
Application system: also called data processing system,
which can be an application or database, depending on
the application. The application software initiates all
readers and tags activities. RFID provides a quick,
flexible, and reliable way for electronically detecting,
tracking and controlling a variety of items. RFID systems
use radio transmissions to send energy to a RFID tag
while the tag emits a unique identification code back to a
data collection reader linked to an information
management system. The data collected from the tag can
then be sent either directly to a host computer, or stored in
a portable reader and up-loaded later to the host
computer.
