Wednesday, August 21, 2019

Spiderman : Homeless Recent Buzz about the Exit of Spiderman Franchise from MCU

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In a Sony statement to USA TODAY Tuesday night, the studio said the outstanding issue remained over the future involvement of Marvel President, and comic movie mastermind, Kevin Feige as producer in future Spider-man films.

 
So when the two companies agreed to share his rights in 2015, it felt like a homecoming -- Spider-Man was finally able to appear in films in the Marvel Universe.
Now played by Tom Holland, the character has appeared in five Marvel movies since that deal -- most recently this year's "Spider-Man: Far From Home."



 If Sony and Disney can't come to a deal, Spidey might not be in Marvel movies in the near future – but he probably wouldn't be anyway, unless for some reason he was supposed to be in "Black Widow" or "The Eternals," the MCU's next two films (which is highly doubtful). There's plenty of time to work stuff out.

Pulo Cinta Resort is an Indonesian Maldives

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Pulo Cinta has a very unique historical story. Once upon a time during the Dutch colonial era, this island became a place of escape between the Prince of Gorontalo and the daughter of one of the Dutch traders. When that war broke out and was expelled from the local community. As a result their love is not condoned. They finally chose to break away and isolate the Pulo Cinta.
 

The Pulo Cinta natural tourism destination is perfect as a honeymoon spot for a new friend to get married, this Gorontalo island is located in Tomini Bay, Patoameme Village, Botumoito District, Boalemo Regency, Gorontalo Province, North Sulawesi. The distance is indeed quite far, if calculated travel from the city of Gorontalo which is about 115 kilometers or takes about 3 hours by road or any bay.
 


To visit Pulo Cinta, you have to take a flight to Jalaluddin Airport and continue the journey to Bolihutuo Beach. Only then will you board the ship for approximately 15 minutes to reach this Pulo Cinta.
 

Mini Africa Savanna in Wonderful Indonesia "Baluran National Park"

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 Baluran National Park protects pasture animals such as buffalo, buffalo, deer, long-tailed monkey and long-tailed bird, peacock. You can see where they are grazing in the middle of the savanna. Every now and then, a herd of deer will cross your vehicle that is passing the road. This scene is often found in pastures like this. It is as if you will be taken far to jump to Africa with such a situation.

 

The area of ​​Baluran National Park is 25 thousand hectares. The location of Baluran National Park is included in Wonorejo village, Banyuputih sub-district, Situbondo district, East Java. Actually, this Baluran area is located on the border of Situbondo and Banyuwangi districts. Many people call the Baluran Situbondo National Park, others also call the Baluran Banyuwangi National Park. It's simple, because the location of this park is closer to Banyuwangi than Situbondo district.

For ticket prices on domestic weekdays, Rp. 15,000 per day and abroad Rp. 150,000 per day, groups of students or students Rp. 8,000 per day, 2 wheels Rp. 5,000 per day, 4 wheels Rp. 10,000 per day, minbus or trucks Rp. 50,000 per day.

On domestic holidays Rp. 17,500 per day, foreign countries Rp. 225,000 per day, student groups or students Rp. 9,500 per day. 2 wheel Rp 7,500 per day, car Rp 15,000 per day, minibus or truck Rp 75,000 per day.




Tuesday, August 20, 2019

Most Romantic married Dwayne Johnson and Lauren Hashian

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Dwayne Johnson was born in Hayward, California, United States, May 2, 1972.
47 years old is an American actor and professional wrestler at WWE known 
as "The Rock". recently conducted a romantic marriage with an actress
named Lauren Hashian. He announced the news in an Instagram post,
featuring the couple with their arms above their heads and giant smiles
plastered on their faces.Pink and blue clouds are scattered above an
ocean backdrop, and the caption is simple: "We do. August 18th, 2019.
Hawaii. Pmamaʻi (blessed)."Johnson and Hashian, 34, first met in 2006
while the actor was filming The Game Plan and started dating in 2007.
They share daughters Jasmine, 3, and Tiana, 16 months.

Wednesday, October 16, 2013

Configure IP address on router using the Setup command

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[admin@MikroTik] > setup
  Setup uses Safe Mode. It means that all changes that are made during setup
are reverted in case of error, or if [Ctrl]+[C] is used to abort setup. To keep
changes exit setup using the [X] key.

[Safe Mode taken]
  Choose options by pressing one of the letters in the left column, before
dash. Pressing [X] will exit current menu, pressing Enter key will select the
entry that is marked by an '*'. You can abort setup at any time by pressing
[Ctrl]+[C].
Entries marked by '+' are already configured.
Entries marked by '-' cannot be used yet.
Entries marked by 'X' cannot be used without installing additional packages.
   r - reset all router configuration
 + l - load interface driver
 * a - configure ip address and gateway
   d - setup dhcp client
   s - setup dhcp server
   p - setup pppoe client
   t - setup pptp client
   x - exit menu
your choice [press Enter to configure ip address and gateway]: a

To configure IP address and gateway, press a or [Enter], if the a choice is marked with an asterisk symbol ('*').

 * a - add ip address
 - g - setup default gateway
   x - exit menu
your choice [press Enter to add ip address]: a

Choose a to add an IP address. At first, setup will ask you for an interface to which the address will be assigned. If the setup offers you an undesirable interface, erase this choice, and press the [Tab] key twice to see all available interfaces. After the interface is chosen, assign IP address and network mask on it:

your choice: a
enable interface:
ether1  ether2  wlan1
enable interface: ether1
ip address/netmask: 10.1.0.66/24
#Enabling interface
/interface enable ether1
#Adding IP address
/ip address add address=10.1.0.66/24 interface=ether1 comment="added by setup"
 + a - add ip address
 * g - setup default gateway
   x - exit menu
your choice: x

basic configuration the Mikrotik

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Before configuring the IP addresses and routes please check the /interface menu to see the list of available interfaces. If you have Plug-and-Play cards installed in the router, it is most likely that the device drivers have been loaded for them automatically, and the relevant interfaces appear on the /interface print

[admin@MikroTik] interface> print
Flags: X - disabled, D - dynamic, R - running
 #    NAME                         TYPE             RX-RATE    TX-RATE    MTU
 0  R ether1                       ether            0          0          1500
 1  R ether2                       ether            0          0          1500
 2 X  wavelan1                     wavelan          0          0          1500
 3 X  prism1                       wlan             0          0          1500
[admin@MikroTik] interface>
The interfaces need to be enabled, if you want to use them for communications. Use the /interface enable name command to enable the interface with a given name or number, for example:

[admin@MikroTik] interface> print
Flags: X - disabled, D - dynamic, R - running
 #    NAME                         TYPE             RX-RATE    TX-RATE    MTU
 0 X  ether1                       ether            0          0          1500
 1 X  ether2                       ether            0          0          1500
[admin@MikroTik] interface> enable 0
[admin@MikroTik] interface> enable ether2
[admin@MikroTik] interface> print
Flags: X - disabled, D - dynamic, R - running
 #    NAME                         TYPE             RX-RATE    TX-RATE    MTU
 0  R ether1                       ether            0          0          1500
 1  R ether2                       ether            0          0          1500
[admin@MikroTik] interface>

Basics proxy setup for beginners

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Normally you connect to the router by IP addresses with any telnet or SSH
client software (a simple text-mode telnet client is usually called telnet and
is distributed together with almost any OS). You can also use graphical
configuration tool for Windows (also can be run in Linux using Wine) called
Winbox. To get Winbox, connect to the router's IP address with a web
browser, and follow the link to download winbox.exe from the router.
MAC-telnet is used to connect to a router when there is no other way to
connect to it remotely if the router has no IP address or in case of
misconfigured firewall. MAC-telnet can only be used from the same
broadcast domain (so there should be no routers in between) as any of the
router's enabled interfaces (you can not connect to a disabled interface).
MAC-telnet program is a part of the Neighbor Viewer. Download it from
www.mikrotik.com, unpack both files contained in the archive to the same
directory, and run NeighborViewer.exe. A list of MikroTik routers working in
the same broadcast domain will be showed double-click the one you need to
connect to. Note that Winbox is also able to connect to routers by their MAC
addresses, and has the discovery tool built-in.
You can also connect to the router using a standard DB9 serial null-modem
cable from any PC. Default settings of the router's serial port are 9600 bits/s
(for RouterBOARD 500 series - 115200 bits/s), 8 data bits, 1 stop bit, no
parity, hardware (RTS/CTS) flow control. Use terminal emulation program
(like HyperTerminal or SecureCRT in Windows, or minicom in UNIX/Linux) to
connect to the router. The router will beep twice when booted up, and you
should see the login prompt shortly before that (check cabling and serial
port settings if you do not see anything in the terminal window).
log/ -- System logs
quit -- Quit console
radius/ -- Radius client settings
certificate/ -- Certificate management
special-login/ -- Special login users
redo -- Redo previously undone action
driver/ -- Driver management
ping -- Send ICMP Echo packets
setup -- Do basic setup of system
interface/ -- Interface configuration
password -- Change password
undo -- Undo previous action
port/ -- Serial ports
import -- Run exported configuration script
snmp/ -- SNMP settings
user/ -- User management
file/ -- Local router file storage.
system/ -- System information and utilities
queue/ -- Bandwidth management
ip/ -- IP options
tool/ -- Diagnostics tools
ppp/ -- Point to Point Protocol
routing/ -- Various routing protocol settings
export --
[admin@MikroTik] ip>
.. -- go up to root
service/ -- IP services
socks/ -- SOCKS version 4 proxy
arp/ -- ARP entries management
upnp/ -- Universal Plug and Play
dns/ -- DNS settings
address/ -- Address management
accounting/ -- Traffic accounting
the-proxy/ --
vrrp/ -- Virtual Router Redundancy Protocol
pool/ -- IP address pools
packing/ -- Packet packing settings
neighbor/ -- Neighbors
route/ -- Route management
firewall/ -- Firewall management
dhcp-client/ -- DHCP client settings
dhcp-relay/ -- DHCP relay settings
dhcp-server/ -- DHCP server settings
hotspot/ -- HotSpot management
ipsec/ -- IP security
web-proxy/ -- HTTP proxy
export --
[admin@MikroTik] ip>


MAC-telnet is used to connect to a router when there is no other way to
connect to it remotely if the router has no IP address or in case of
misconfigured firewall. MAC-telnet can only be used from the same
broadcast domain (so there should be no routers in between) as any of the
router's enabled interfaces (you can not connect to a disabled interface).
MAC-telnet program is a part of the Neighbor Viewer. Download it from
www.mikrotik.com, unpack both files contained in the archive to the same
directory, and run NeighborViewer.exe. A list of MikroTik routers working in
the same broadcast domain will be showed double-click the one you need to
connect to. Note that Winbox is also able to connect to routers by their MAC
addresses, and has the discovery tool built-in.
You can also connect to the router using a standard DB9 serial null-modem
cable from any PC. Default settings of the router's serial port are 9600 bits/s
(for RouterBOARD 500 series - 115200 bits/s), 8 data bits, 1 stop bit, no
parity, hardware (RTS/CTS) flow control. Use terminal emulation program
(like HyperTerminal or SecureCRT in Windows, or minicom in UNIX/Linux) to
connect to the router. The router will beep twice when booted up, and you
should see the login prompt shortly before that (check cabling and serial port settings if you do not see anything in the terminal window).

Wednesday, September 18, 2013

The purpose programming language design

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  • A good language should be easy to compile.
  • Not complicate the compilation process.
  • Complexity can arise because of the symbol
  • have different meanings.
  • Example signs parenthesis (brackets open / close):
Grouping sub-expression Restricted arguments in the function / procedureIndex on the arrays (in VB) Expression of mathematics and logic Examples of simple but powerful scheme are passing parameters by value and by reference.

What Role Did She Play in Miley-Liam Split? : January Jones

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At least one tabloid has said Hemsworth was caught cheating with Eiza Gonzalez over the weekend, a Mexican singer/actress with whom he hooked up in Las Vegas.
But other reports have claimed tension between Liam and Miley for weeks, dating back to the latter's lewd Video Music Awards performance and continuing when Cyrus went naked for her "Wrecking Ball" video.
Then there's January Jones.
Rumors first surfaced in February that Liam swapped spit with the Mad Men actress at a Vanity Fair party, while an insider alleges the two have kept in contact ever since... especially dirty contact, that is!
More than one source says Hemsworth texted Jones that he wants to "f-ck" her, while Us Weekly quotes a friend of the star's who backs up this allegation and adds that "January thinks Liam is so sexy."
Liam Hemsworth was reportedly pursuing Mad Men’s January Jones, while his relationship with his 20-year-old fiancee crumbled in recent months.
A source told Us magazine that Jones thinks that The Hunger Games actor is very sexy.
Earlier this summer, Hemsworth had also sent the 35-year-old single mum, a graphic sexual message, which read the he wants to “**** her”.
The Mad Men star was earlier linked to Miley Cyrus’ former fiancee in February, when the two of them were spotted leaving West Hollywood hotspot, ‘Chateau Marmont,’ together.
A source had then revealed that Jones and Hemsworth were “all over each other” at a house party that night, though the 23-year-old actor denied the rumours.
Though a rep had recently hit out at claims Liam had been pursing the actress, insisting to GossipCop the rumours were "tabloid fiction," sources recently told Us Weekly the actor had once again been after her.  "January thinks Liam is so sexy," a source told Us Weekly, claiming the couple were "all over each other," on the infamous night out at the Chateau Marmont.

Hamming code

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Hamming code
Richard Hamming invented at Bell Labs in 1950
Error detection mechanisms by adding a data word (D) with a code, usually a parity check bit (C).
The data stored in length D + C.
Known errors by analyzing the data and parity bits

# Data Bits
# Bit Paritas SEC
# Bit Paritas DEC
8
4
5
16
5
6
32
6
7
64
7
8
128
8
9
512
9
10

Parity check bits are placed with 2N formulation where
Each check bit (C) operates in every bit position data position number 1 in the column contains numbers
Data enter: 00111001 then change the data bits to 3 from 0 to 1 as its error.

how to get the data bits to 3 bits as there are errors?

  N = 0,1,2, ……, while the remaining bits of the data is. Then the exclusive-OR sum::
  C1 = D1 Å D2 Å D4 Å D5 Å D7
  C2 = D1 Å D3 Å D4 Å D6 Å D7
  C4 = D2 Å D3 Å D4 Å D8
  C8 = D5 Å D6 Å D7 Å D8
answer:
Enter data into the formulation of the parity check bits :
C1 = 1 Å 0 Å 1 Å 1 Å 0   = 1
C2 = 1 Å 0 Å 1 Å 1 Å 0   = 1
C4 = 0 Å 0 Å 1 Å 0   = 1
C8 = 1 Å 1 Å 0 Å 0   = 0
Now bit 3 having a data error : 00111101
C1 = 1 Å 0 Å 1 Å 1 Å 0   = 1
C2 = 1 Å 1 Å 1 Å 1 Å 0   = 0
C4 = 0 Å 1 Å 1 Å 0   = 0
C8 = 1 Å 1 Å 0 Å 0   = 0

Query for checking

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/*before running this script run the report from backoffice first to store the data to table itemsales*/
/*this query will find out variance between sales after tax/gross sales and collected*/


--1.run this script to group all item per salesno
SELECT salesno,splitno,
Sum(([ItemSales].[Quantity]*[ItemSales].[ItemAmount])*case when
([ItemSales].[TransMode]='REG') then 1 else -1 end *case when ((FunctionID)=26)
then 1 else 0 end ) AS ItemSales,
Sum(((Discount)+(PromotionSaving))*case when
((FunctionID)=26) then 1 else 0 end *case when ((DiscountType)<>'FOC Item') then
1 else 0 end *case when ((TransMode)='REG') then 1 else -1 end ) AS ItemDisc,
Sum((ItemAmount)*case when ((FunctionID)=25) then 1 else 0 end *case when
((TransMode)='REG') then 1 else -1 end ) AS BillDisc,
(
Sum(([ItemAmount]*[Quantity])*case when (([FOCType])='FOC Item') then 1 else 0
end *case when ((FunctionID)=26) then 1 else 0 end *case when
(([TransMode])='REG') then 1 else -1 end )) AS TFOC,
Sum(([ItemAmount])*case
when ((FunctionID)=7) then 1 else 0 end *case when (([TransMode])='REG') then 1
else -1 end ) AS BFOC, Sum((Tax0)*case when ((TransMode)='REG') then 1 else -1
end ) AS TTax0,
Sum((Tax1)*case when ((TransMode)='REG') then 1 else -1 end
*case when FunctionID=1  or FunctionID=2  or FunctionID=3  or FunctionID=4  or
FunctionID=5  or FunctionID=6  or FunctionID=8  or FunctionID=9  then 1 else 0
end ) AS TTax1,
Sum((Gratuity)*case when ((TransMode)='REG') then 1 else -1 end
) AS TGratuity,
Sum((RndingAdjustments)*case when ((TransMode)='REG') then 1
else -1 end ) AS TRndAdj,
Sum(([ItemAmount]+[Gratuity])*case when FunctionID=1
or FunctionID=2  or FunctionID=3  or FunctionID=4  or FunctionID=5  or
FunctionID=6  or FunctionID=8  or FunctionID=9  then 1 else 0 end *case when
(([TransMode])='REG') then 1 else -1 end ) AS Collected,
Sum(([ItemSales].[Covers])*case when ([ItemSales].[TransMode]='REG') then 1 else
-1 end *case when ([ItemSales].[TransStatus]='S') then 1 else 0 end ) AS
TCovers, Sum(([ItemSales].[Quantity])*case when ([ItemSales].[TransMode]='REG')
then 1 else -1 end *case when ([ItemSales].[TransStatus]='S') then 1 else 0 end
) AS TBills
, Sum(RndingAdjustments) as RndingAdjustments
into #tot
FROM ItemSales WHERE ((ItemSales.TransStatus)=' ') OR
((ItemSales.TransStatus)='S') or ((Itemsales.TransStatus)='E')
group by salesno,splitno


--2.run this script to get netsales and tax
select salesno,itemsales,itemsales-itemdisc-billdisc-tfoc-bfoc as netsales,collected-RndingAdjustments as collected,tgratuity,ttax0,ttax1
into #tot2
from #tot

--3.a run this script for exclusive tax
select salesno,itemsales,netsales+ttax0+ttax1+tgratuity as NetAndTax,collected
into #tot3
from #tot2

--3.b run this script for inclusive tax
select salesno,itemsales,netsales+tgratuity as NetAndTip,collected
into #tot3
from #tot2

--4.run this script to find out the variance
select * from #tot3
where netandtax<>collected


/*after you find out wrong salesno,go to salesitemstemp and anlyze the data to find out the wrong record*/

Tuesday, August 24, 2010

Duplex Settings

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There are two types of duplex settings used for communications on an Ethernet network: half duplex and full duplex. The figure shows the two duplex settings available on modern network equipment.

Half Duplex: Half-duplex communication relies on unidirectional data flow where sending and receiving data are not performed at the same time. This is similar to how walkie-talkies or two-way radios function in that only one person can talk at any one time. If someone talks while someone else is already speaking, a collision occurs. As a result, half-duplex communication implements CSMA/CD to help reduce the potential for collisions and detect them when they do happen. Half-duplex communications have performance issues due to the constant waiting, because data can only flow in one direction at a time. Half-duplex connections are typically seen in older hardware, such as hubs. Nodes that are attached to hubs that share their connection to a switch port must operate in half-duplex mode because the end computers must be able to detect collisions. Nodes can operate in a half-duplex mode if the NIC card cannot be configured for full duplex operations. In this case the port on the switch defaults to a half-duplex mode as well. Because of these limitations, full-duplex communication has replaced half duplex in more current hardware.

Full Duplex: In full-duplex communication, data flow is bidirectional, so data can be sent and received at the same time. The bidirectional support enhances performance by reducing the wait time between transmissions. Most Ethernet, Fast Ethernet, and Gigabit Ethernet NICs sold today offer full-duplex capability. In full-duplex mode, the collision detect circuit is disabled. Frames sent by the two connected end nodes cannot collide because the end nodes use two separate circuits in the network cable. Each full-duplex connection uses only one port. Full-duplex connections require a switch that supports full duplex or a direct connection between two nodes that each support full duplex. Nodes that are directly attached to a dedicated switch port with NICs that support full duplex should be connected to switch ports that are configured to operate in full-duplex mode.

Standard, shared hub-based Ethernet configuration efficiency is typically rated at 50 to 60 percent of the 10-Mb/s bandwidth. Full-duplex Fast Ethernet, compared to 10-Mb/s bandwidth, offers 100 percent efficiency in both directions (100-Mb/s transmit and 100-Mb/s receive).

key elements ethernet 802.3 networks

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In this topic, you will learn about key components of the Ethernet standard that play a significant role in the design and implementation of switched networks. You will explore how Ethernet communications function and how switches play a role in the communication process.

CSMA/CD

Ethernet signals are transmitted to every host connected to the LAN using a special set of rules to determine which station can access the network. The set of rules that Ethernet uses is based on the IEEE carrier sense multiple access/collision detect (CSMA/CD) technology. You may recall from CCNA Exploration: Networking Fundamentals that CSMA/CD is only used with half-duplex communication typically found in hubs. Full-duplex switches do not use CSMA/CD.

Carrier Sense

In the CSMA/CD access method, all network devices that have messages to send must listen before transmitting.

If a device detects a signal from another device, it waits for a specified amount of time before attempting to transmit.

When there is no traffic detected, a device transmits its message. While this transmission is occurring, the device continues to listen for traffic or collisions on the LAN. After the message is sent, the device returns to its default listening mode.

Multi-access

If the distance between devices is such that the latency of the signals of one device means that signals are not detected by a second device, the second device may also start to transmit. The media now has two devices transmitting signals at the same time. The messages propagate across the media until they encounter each other. At that point, the signals mix and the messages are destroyed, a collision. Although the messages are corrupted, the jumble of remaining signals continues to propagate across the media.

Collision Detection

When a device is in listening mode, it can detect when a collision occurs on the shared media, because all devices can detect an increase in the amplitude of the signal above the normal level.

When a collision occurs, the other devices in listening mode, as well as all the transmitting devices, detect the increase in the signal amplitude. Every device that is transmitting continues to transmit to ensure that all devices on the network detect the collision.

Jam Signal and Random Backoff

When a collision is detected, the transmitting devices send out a jamming signal. The jamming signal notifies the other devices of a collision, so that they invoke a backoff algorithm. This backoff algorithm causes all devices to stop transmitting for a random amount of time,  which allows the collision signals to subside.

After the delay has expired on a device, the device goes back into the "listening before transmit" mode. A random backoff period ensures that the devices that were involved in the collision do not try to send traffic again at the same time, which would cause the whole process to repeat. However, during the backoff period, a third device may transmit before either of the two involved in the collision have a chance to re-transmit.

Ethernet Communications

Reference the selected Ethernet Communications area in the figure.

Communications in a switched LAN network occur in three ways: unicast, broadcast, and multicast:

Unicast: Communication in which a frame is sent from one host and addressed to one specific destination. In unicast transmission, there is just one sender and one receiver. Unicast transmission is the predominant form of transmission on LANs and within the Internet. Examples of unicast transmissions include HTTP, SMTP, FTP, and Telnet.

Broadcast: Communication in which a frame is sent from one address to all other addresses. In this case, there is just one sender, but the information is sent to all connected receivers. Broadcast transmission is essential when sending the same message to all devices on the LAN. An example of a broadcast transmission is the address resolution query that the address resolution protocol (ARP) sends to all computers on a LAN.

Multicast: Communication in which a frame is sent to a specific group of devices or clients. Multicast transmission clients must be members of a logical multicast group to receive the information. An example of multicast transmission is the video and voice transmissions associated with a network-based, collaborative business meeting.

Ethernet Frame

The first course in our series, CCNA Exploration: Networking Fundamentals, described the structure of the Ethernet frame in detail. To briefly review, the Ethernet frame structure adds headers and trailers around the Layer 3 PDU to encapsulate the message being sent. Both the Ethernet header and trailer have several sections (or fields) of information that are used by the Ethernet protocol. The figure shows the structure of the current Ethernet frame standard, the revised IEEE 802.3 (Ethernet).

Roll over each field name to see its description.

Preamble and Start Frame Delimiter Fields

The Preamble (7 bytes) and Start Frame Delimiter (SFD) (1 byte) fields are used for synchronization between the sending and receiving devices. These first 8 bytes of the frame are used to get the attention of the receiving nodes. Essentially, the first few bytes tell the receivers to get ready to receive a new frame.

Destination MAC Address Field

The Destination MAC Address field (6 bytes) is the identifier for the intended recipient. This address is used by Layer 2 to assist a device in determining if a frame is addressed to it. The address in the frame is compared to the MAC address in the device. If there is a match, the device accepts the frame.

Source MAC Address Field

The Source MAC Address field (6 bytes) identifies the frame's originating NIC or interface. Switches use this address to add to their lookup tables.

Length/Type Field

The Length/Type field (2 bytes) defines the exact length of the frame's data field. This field is used later as part of the Frame Check Sequence (FCS) to ensure that the message was received properly. Only a frame length or a frame type can be entered here. If the purpose of the field is to designate a type, the Type field describes which protocol is implemented. When a node receives a frame and the Length/Type field designates a type, the node determines which higher layer protocol is present. If the two-octet value is equal to or greater than 0x0600 hexadecimal or 1536 decimal, the contents of the Data Field are decoded according to the protocol indicated; if the two-byte value is less than 0x0600 then the value represents the length of the data in the frame.

Data and Pad Fields

The Data and Pad fields (46 to 1500 bytes) contain the encapsulated data from a higher layer, which is a generic Layer 3 PDU, or more commonly, an IPv4 packet. All frames must be at least 64 bytes long (minimum length aides the detection of collisions). If a small packet is encapsulated, the Pad field is used to increase the size of the frame to the minimum size.

Frame Check Sequence Field

The FCS field (4 bytes) detects errors in a frame. It uses a cyclic redundancy check (CRC). The sending device includes the results of a CRC in the FCS field of the frame. The receiving device receives the frame and generates a CRC to look for errors. If the calculations match, no error has occurred. If the calculations do not match, the frame is dropped.

MAC Address

In CCNA Exploration: Networking Fundamentals, you learned about the MAC address. An Ethernet MAC address is a two-part 48-bit binary value expressed as 12 hexadecimal digits. The address formats might be similar to 00-05-9A-3C-78-00, 00:05:9A:3C:78:00, or 0005.9A3C.7800.

All devices connected to an Ethernet LAN have MAC-addressed interfaces. The NIC uses the MAC address to determine if a message should be passed to the upper layers for processing. The MAC address is permanently encoded into a ROM chip on a NIC. This type of MAC address is referred to as a burned in address (BIA). Some vendors allow local modification of the MAC address. The MAC address is made up of  OUI numbers. Within the OUI, there are 2 bits that have meaning only when used in the destination address, as follows:

Broadcast or multicast bit: Indicates to the receiving interface that the frame is destined for all or a group of end stations on the LAN segment.

Locally administered address bit: If the vendor-assigned MAC address can be modified locally, this bit should be set.

Vendor Assignment Number

The vendor-assigned part of the MAC address is 24 bits long and uniquely identifies the Ethernet hardware. It can be a BIA or modified by software indicated by the local bit.
 
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