IoT stack vs Web stack-difference between IoT stack and Web stack
This page compares IoT stack vs Web stack and mentions tabular difference between IoT stack and Web stack.
Introduction:
Let us first understand difference between OSI stack vs TCPIP stack.
As shown in the figure-1 below, OSI (Open System Interconnection) has 7 layers while
TCPIP has 4 layers as shown. Let us understand very basic functions of each
of these 7 OSI layers from top to bottom. Please note that these layers are
present on both the transmit side as well as receive side of the networking
device. As all the devices perform transmit and receive functionalities,
the 7 OSI layers have both Tx/Rx functionalities as a whole in all the networking
devices.
• Application: The data to be trasmitted is
obtained from this layer with the help of various applications such as
web, ftp, telnet etc. These applications will have data in different formats such as
binary, ASCII, EBCDIC etc.
• Presentation: It does syntax conversion (such as binary to ascii )
as well as performs encryption/decryption of the data.
• Session: It takes care of session management which is
very useful for operators to charge the subscribers as per their billing period.
• Transport: It does flow control, fragmentation, reassembly of
the data to be transmitted or received.
• Network: It takes care of routing of the packets as per logical addressing (i.e. as per
IPv4 and IPv6 assignments). Various routing protocols exist in different technologies
such as RIP, OSPF, AODV etc.
• Datalink: It takes care of error control and flow control.
It provides retransmission capabilities in case of faulty received packets with the
help of ARQ protocol. The other main job of datalink layer is to provide medium access control and management
of the medium (wired or wireless) supported by physical layer interface. Hence it is known as MAC layer also.
• Physical: This layer is responsible for transmission of data over physical layer
medium (wired or wireless). The layer will have functionalities such as modulation-demodulation,
FEC (forward error correction) etc. The most common FEC modules are convolution encoder at
Tx side and viterbi decoder at Rx side. Advanced modulation schemes such as OFDM, OFDMA are also used to obtain
high data rates. Refer OSI vs TCPIP>> for further study
on data flow across these layers.
IoT Stack vs Web Stack
The figure-2 depicts IoT stack vs Web stack. Following table summarizes difference between IoT stack and Web stack with reference to functionalities at different layers. Physical layer and MAC layer of IoT (Internet of Things) stack varies as per wired or wireless technologies used. There are numerous IoT wireless technologies whose links are mentioned at the bottom for further study.
| Features | IoT Stack | Web Stack |
|---|---|---|
| Function or application | It is used in constrained network having low power, low bandwidth and low memory requirements. | It is used in non-constrained network having no limits on power/BW/memory. |
| Size of data to be transported | tens of bytes | hundreds or thousands of bytes |
| Data format | It uses CBOR (Concise Binary Object Representation) format as IoT is used for tiny messages. CBOR is based on JSON though CBOR uses binary encoding while JSON uses text encoding. | It uses HTML, XML and JSON formats. |
| Application Layer | It uses CoAP protocol at application layer. | It uses HTTP protocol at application layer. |
| Transport layer | It uses UDP which is faster due to smaller header size compare to TCP. It is lighter protocol compare to TCP. | It uses TCP which is connection oriented and slower compare to UDP. |
| Security layer | It uses DTLS (Datagram Transport Layer Security) protocol for security. | It uses TLS/SSL protocols for the same. |
| Internet layer | It uses 6LoWPAN to convert large IPv6 packets into small size packets to be carried on wireless medium as per bluetooth, zigbee etc. standards. It does fragmentation and reassembly. It also does header compression to reduce packet size. | It does not require protocols like 6LoWPAN. Fragmentation and reassembly is taken care by transport layer (i.e. TCP) itself. |
| Datalink or MAC layer | It will have MAC layer as per IoT wireless technology used viz. bluetooth, zigbee, zwave etc. It takes care of medium access control and resource allocation and management. | It will have MAC layer as per LAN or WLAN or DSL or ISDN technologies. |
| Physical layer and Radio Frequency (RF) layer | It will have physical layer (baseband) as per IoT wireless technologies viz. bluetooth, zigbee, zwave etc. It uses frequencies as per cellular or indoor wireless technologies and country wide allocations for the same. | It will have PHY layer as per LAN or WLAN or DSL or ISDN technologies. |
Refer IoT protocol stack >> which defines 7 layers of IoT with its functions and protocols/technologies used.