Protocols: non-cyber examples from everyday life
One way to get the idea of computer protocols and their purpose is to consider some non-computer protocols with which you are already familiar. Here are three examples of generally familiar non-cyber protocols:
climbing signals used by mountaineers ("climbing"... "climb")
"prowords" used in radio conversations ("over"... "roger")
social etiquette rules for meeting other people (offer hand... shake hand)
These are all highly defined forms of systematic exchange. They are interactive. It is the substance and sequence of interaction that a protocol defines. (Or, that "substance and sequence" is what the protocol is.) The first step to understanding computer protocols is perhaps recognizing their great similarity to such non-computer counterparts as these.
1. Climbing signals
From Mountaineering: the Freedom of the Hills
"Effective communication between climber and belayer is essential for safety and efficiency. Over the years climbers have developed a set of universally accepted rope signals, each with a different sound so that even wind-garbled words can be interpreted correctly."
2. Radio Communication Prowords
Radio users punctuate their conversations with "prowords." (Perhaps the term stems from "protocol words." )
Prowords are commonly used
|Affirmative||Yes||Number||Messsage number follows|
|All After||Say again all after ______||Out||End of transmission (Final)|
|All Before||Say again all before _____||Over||End of Tranmission (Please reply)|
|Break||Used to seperate message parts||Roger||I copy your transmission|
|Break||Stop Transmitting||Say Again||Repeat your transmission|
|Correct||That is Correct||Slant||Slant Bar|
|Figures||Numerals Follow||This Is||This transmission is from____|
|From||Message originator follows||Time||File or date time of message follows|
|Groups||Number of words follows||To||Addressee Follows|
|Incorrect||That is Incorrect||Wait||Short Pause|
|Initial||Single letter follows||Wait out||Long Pause|
|I Say Again||I repeat||Word after||Say again after the word ______|
|I spell||Phonetic Spelling Follows||Word before||Say again before the word______|
|Message Follows||Prepare to copy message|
|More to follow||Standby, More traffic for you|
|Negative||No, Not received||Mars - Army Radiotelephone Prowords|
How do I
say what I want?
First, say who you are calling, three times...
example: "Coast Guard Station Channel Islands, Coast Guard Station
Channel Islands, Coast Guard Station Channel Islands""
2. Then immediately identify the station calling and what channel you are calling from (If you have reason to believe that the recipient is busy and monitoring multiple channels. The Coast Guard does this). Their scanner may continue scanning before he/she looks at the display. Most kayaks don't have names, so make one up and use it consistently, at least during the duration of a call or emergency. You can call your boat (almost) anything you want. Technically, the name should be written on the boat in bold letters, that way the authorities will know what to put in their report if they find no survivors...
example: "This is Yellow Yak, Yellow Yak, on channel 16, over "
Always say "over" when you are done with a transmission, to
indicate that you await a response. Say "out" when you are ready to
end a conversation. Never say "over and out."
That is redundant, confusing and the hallmark of a rank amateur
who stays up too late at night watching old, but misleading movies.
3. Wait for an answer. Try twice again in a minute or two apart if
there is no response. You might then try another channel or wait a while
and try again, remembering not to hog the channel unless it is a DIRE
emergency, then all bets are off.
Hopefully, you will get a response, such as: "Yellow Yak, this
is Channel Islands Coast Guard, over" They might also add something like "Please switch to
You should say something to acknowledge that, like "Channel Islands Coast Guard, This is Yellow Yak, Yellow Yak. WILCO (will comply), switching to channel XX, out" Then do it and call them right back, after checking that the channel is open, usually without repeating everything three times again...
4. Get to the meat of
your call. Example: "Channel Islands Coast Guard, we have spotted a
red Personal Water Craft on fire and sinking, approximately one mile
southeast of the Ventura Harbor Breakwater. Approximate position is
thirty-four degrees, fourteen minutes North and one hundred nineteen
degrees, seventeen minutes West.
There appear to be two people in the water, no apparent injuries
and no PFD’s. Will attempt to render assistance, but request that you
send rescue support, over"
Listen for their response, example: "Yellow Yak, Yellow Yak, your
signal is weak. Confirming message: you spotted blue Personal Water
Craft on fire and sinking, approximately one mile southeast of Ventura
Harbor Breakwater. Approximate position is thirty-four degrees, fourteen
minutes North latitude. Could not copy longitude. Please say again
longitude. Two people in water, no injuries. Will you bring them ashore?
You answer: "Coast Guard Station Channel Islands. Negative. I say
again, that's a RED PWC, longitude is one hundred nineteen degrees,
seventeen minutes West. Cannot bring them to shore or tow their craft.
We are a seventeen foot kayak. No room aboard. We can stand by for
awhile and try to keep them safe, but weather is deteriorating. Winds
are Northwest at 20 knots, eight foot combined seas and whitecaps, so
please hurry. What is your ETA? over."
They respond. "Yellow Yak, Estimated Arrival time is forty four
minutes, can you hold on, over?
You respond: "Coast Guard Channel Islands, Yellow Yak acknowledges
your ETA of forty four minutes, please allow for estimated drift of 1-2
knots to Southeast, thank you, out."
Then you hear: "Yellow Yak, Yellow Yak, Yellow Yak, this is Carol Ann,
" Carol Ann, this is Yellow Yak, please switch to channel XX,
They say: "Yellow Yak, this is Carol Ann, switching to XX, out"
say: "Yellow Yak, Yellow Yak, Yellow Yak, this is Carol Ann,
13. You say:
"Carol Ann, this is Yellow Yak, go ahead, please, over."
14. They say:
"We are headed for your position.
Cannot see you. Coming from SouthWest. ETA 7 minutes, estimated range: one
mile. Look for 48" Hatteras Long Range Cruiser, trawler design, white
hull with blue stripe and canvas, over."
say: "Carol Ann, we think we see you. Head about 8-10 degrees more
to starboard. We'll
vector you in. Please monitor channel XX.
say: "Carol Ann, WILCO,
Further conversation might be necessary to coordinate the
approach, take on survivors, set up a salvage/tow, etc.
It would be a good idea to keep the Coast Guard on track until it
can be ascertained that the civilian pleasure craft Carol Ann is
actually capable of effectively rendering assistance in this incident.
3. The Social Etiquette of Meeting
Greetings and Salutations
or, Moving and Shaking Amongst the Nobility of France.
Throughout your travels you will encounter several nobles in several settings. Traditions have been set forth on how to act when you encounter other nobles or even certain locations. The following are some of the guidelines for the etiquette of meeting people.
THE ACTS OF POLITENESS
The following are the proper ways of performing actions of greeting.
It is customary for a gentleman to bow. Generally it is prefered that a gentleman, when bowing, bend at the waste and lower their upper body. If a hat is being worn it should be removed during the act of the bow at least till it clears the head. In most situations one should also nod your head forward when bowing.
It is customary for a lady to curtsey. Generally it is prefered that a lady, when performing a curtsey, bend at the knees and lower her whole body. A lady should hold her skirts, if wearing them, so that they do not gather on the ground. The back should be held as straight as possible. In most situations one should also nod your head forward when performing a curtsey.
A gentleman kneels at the end of a bow, lowering down to their right knee. A lady kneels as a conclusion of the curtsey, bending her knees all the way until they touch the ground. A lady is not required to fully kneel outdoors, especially if conditions are muddy (Though a true gentleman would provide a suitable surface for a lady by throwing down a cloak). When kneeling, one should nod their head forward and keep it there, looking no higher than the knees of the one you are kneeling before.
THE HAND SHAKE
A gentleman will take an offered hand of another gentleman and grip it firmly, not crushingly, and give it a single pump. A gentleman when offered the hand of a lady should take the ladys hand gently in his and either give it a slight squeeze or a respectful, dry kiss on her knuckle. A gentleman never offers his hand to a lady, the lady should offer first, extending her hand, wrist slightly bent and palm down.
Two close individuals, regardless of gender, who meet and give a friendly hug in public are permitted to give a respectful, dry kiss to each others left cheek, or both cheeks. The only time a kiss should be given on the lips in public is at the conclusion of a wedding ceremony or during certain other ceremonies and celebrations, such as New Years. All other shows of affection should be kept out of courtly environments.
A military salute is performed by either sex by bringing the right arm up until it is parallel with the ground and bent so that the tips of the fingers, held ridged, just touch above the right eye. The palm of the hand should be facing directly outwards, not inward. If a soldier is carrying a pole-arm or rifle the salute should be delivered across the chest to the left shoulder, instead of the forehead. Traditionally, a soldier should stand at attention when saluting.