RSA’s Reliability

In principle 2 total 6 number appear

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p     53
　　q     271
　　n     14363
　　φ(n)  14040
　　e     97
　　d     9553

Public key use 2 of them, n and e.
The rest of them do not public. The most important number above
is d, because n and d compose to private key.

Discuss

How to compute d, only know n and e

1. $ed \equiv 1 \quad (mod \quad \phi(n))$
   Only know e and $\phi(n)$ than know what d is,
   among them, e is public.

2. $\phi(n) = (p-1) \times (q-1)$
   Need know what p and q is.

3. $n = p \times q$
   Only n factorization, than got what p q probaly is.

Conclusion: If number n could be factorization, than
d [mod inverse element] could be found.
That mean private key be hacked.

Think

Extremely large number’s mod inverse element possible is extremely large as well. The difficulty in factorizing two coprime number that the mod inverse element possible number mod by public key e rest got 1, the more difficulty it is, the more security key is.

Human’s power only solve number factorization max to 232 in decimal, 768 in binary.
So at present, 768 bits[96 bytes] is the longest RSA key length be breaked.

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12301866845301177551304949
　　58384962720772853569595334
　　79219732245215172640050726
　　36575187452021997864693899
　　56474942774063845925192557
　　32630345373154826850791702
　　61221429134616704292143116
　　02221240479274737794080665
　　351419597459856902143413
   =
33478071698956898786044169
　　84821269081770479498371376
　　85689124313889828837938780
　　02287614711652531743087737
　　814467999489
　　　　×
　　36746043666799590428244633
　　79962795263227915816434308
　　76426760322838157396665112
　　79233373417143396810270092
　　798736308917

Generate cipher code

Step 1 Choose two coprime number randomly

53 and 271

The bigger these number is the more difficulty to break it.

Step 2 First number multiplied by second number

totle 14bits
In daily application use 1024 bits[128bytes] usually.
In some important application use 2048 bits[256bytes] usually.

Step 3 Calculate n’s Euler function

Step 4 Choose a number e

and the number e has coprime relation with

Choose between (1, 14040), suppose 97 as e;

Step 5 Calculate mod inverse element

Calculate the mod inverse element d for e with

->

->

->

Based on Extended Euclidean algorithm
x = -4487, y = 31 -> (-4487, 31) is a solution pair
positive d
(-4487, 31) -> (9553, -66)

Step 6 Packaging

Pack n and e into public key,n and d into private key
n = 14040 e = 97 d = 9953 and k = -66

So , (14363, 97) is public key, (14363, 9553) is private key.

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f = open("out.txt", "a")
for i in range(1,102):
	# something before write here
	if i<10:
		f.write("00")
		f.write(str(i))
		f.write(".jpg\n")
	elif i<100:
		f.write("0")
		f.write(str(i))
		f.write(".jpg\n")
	else:
		f.write(str(i))
		f.write(".jpg\n")
f.close()

• open file get a file variable
• write data from range of int
• after written close file

string -> char bunch slice method
target = src[0:len(src)-5]

History

In 1977, three mathematician Rivest Shamir and Adleman designed the RSA algorithm.

Coprime relation

If two positive integer no other common elements except 1,
then these two number be called have coprime relation.

• any two coprime number compose to coprime relation
• one coprime another is not multiple with the privous one then coprime relation.
• if the bigger one in two number is coprime number, then these two compose to coprime relation.
• 1 with any nature number is coprime relation.
• p is integer bigger than 1, p and p-1 is coprime relation.
• p is odd number bigger than 1, p and p-2 is coprime relation.

Euler formula(function)

Condition 1

1 with any nature number is coprime relation.

Condition 2

If n is coprime number than every number lower than n is coprime relation with n.

Condition 3

If number n is some coprime number’s times square than.

For example:

In 1 -> 16 totle 2^3 is multiple with 2.
So the number coprime relation with 16 is 8;
1 3 5 7 9 11 13 15

Condition 4

If number can be separate into
two number that have coprime relation.

Then:

For example:

Condition 5

Any positive integer can be separate into
a series of coprime number’s accumulate.

based on proposition 4 ->

based on proposition 3->

then ->

This is the Euler’s common formula , for example

Euler proposition

Special Condition
If p is a coprime number than:

• Fermat little theorem
• Fermat euler theorem

Mod inverse element

If two number a and n is coprime relation
than definitely could find a number b that $ab \quad mod \quad n = 1$

Call b is a’s mod reserve element

For example:
3 and 5 is coprime relation , set a=3, n=5, then a’s mod reserve element is 7.
7 {+-} kn[-4, 7, 12, 17] is all a’s mod reserve element.

Euler proposition proves mod reserve element definitely exists.

a^{\phi(5)-1} = 3^3 = 27

$$

javascript advance selector

Define in W3C Selectors API, used to locate element in document by CSS rule.

IE >= 8, Firefox, Chrome, Safari, Opera support them.

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module dom {
  [Supplemental, NoInterfaceObject]
  interface NodeSelector {
     Element querySelector(in DOMString selectors);
     NodeList querySelectorAll(in DOMString selectors);
  };
  Document implements NodeSelector;
  DocumentFragment implements NodeSelector;
  Element implements NodeSelector;
};

Document, DocumentFragment, Element implements NodeSelector interface.
The difference is querySelector return an object, querySelectorAll return a collection(NodeList).

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document.getElementById("test");
document.querySelector("#test");
document.querySelectorAll("#test")[0];

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document.getElementsByClassName('red')
document.querySelector('.red')
document.querySelectorAll('.red')

Difference between jQuery(element).find(selector)

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<div id="test1"><a href="http://www.linchenguang.com/">lcg</a></div>
<p id="bar">I'm a bar</p>

<script>
var d1 = document.getElementById('test1'),
obj1 = d1.querySelector('div a'),
obj2 = d1.querySelectorAll('div a');
obj3 = $(d1).find('div a');
//<a href="http://www.linchenguang.com/">lcg</a>
console.log(obj1)
//1
console.log(obj2.length)
//null
console.log(obj3)
</script>

querySelectorAll find element in DOM, contain Element it’s self.
jQuery(element).find(selector) find element in DOM, not contain Element it’s self.

• In PHP 5.3

imagejpeg($image, '', 100);

• In PHP 5.4

imagejpeg($image, NULL, 100);

• In PHP 5.3

  1	$current_gallery = array_pop(preg_split("/[\/]/", dirname($img)));

• In PHP 5.4

  1 2	$some_path_array = preg_split("/[\/]/", dirname($img)); $current_gallery = array_pop($some_path_array);

Phtoswipe documentation

Primer

Add src

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<!-- Core CSS file -->
<link rel="stylesheet" href="path/to/photoswipe.css">

<!-- Skin CSS file (styling of UI - buttons, caption, etc.)
     In the folder of skin CSS file there are also:
     - .png and .svg icons sprite,
     - preloader.gif (for browsers that do not support CSS animations) -->
<link rel="stylesheet" href="path/to/default-skin/default-skin.css">

<!-- Core JS file -->
<script src="path/to/photoswipe.min.js"></script>

<!-- UI JS file -->
<script src="path/to/photoswipe-ui-default.min.js"></script>

Add tag to DOM

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<!-- Root element of PhotoSwipe. Must have class pswp. -->
<div class="pswp" tabindex="-1" role="dialog" aria-hidden="true">

    <!-- Background of PhotoSwipe.
         It's a separate element as animating opacity is faster than rgba(). -->
    <div class="pswp__bg"></div>

    <!-- Slides wrapper with overflow:hidden. -->
    <div class="pswp__scroll-wrap">

        <!-- Container that holds slides.
            PhotoSwipe keeps only 3 of them in the DOM to save memory.
            Don't modify these 3 pswp__item elements, data is added later on. -->
        <div class="pswp__container">
            <div class="pswp__item"></div>
            <div class="pswp__item"></div>
            <div class="pswp__item"></div>
        </div>

        <!-- Default (PhotoSwipeUI_Default) interface on top of sliding area. Can be changed. -->
        <div class="pswp__ui pswp__ui--hidden">

            <div class="pswp__top-bar">

                <!--  Controls are self-explanatory. Order can be changed. -->

                <div class="pswp__counter"></div>

                <button class="pswp__button pswp__button--close" title="Close (Esc)"></button>

                <button class="pswp__button pswp__button--share" title="Share"></button>

                <button class="pswp__button pswp__button--fs" title="Toggle fullscreen"></button>

                <button class="pswp__button pswp__button--zoom" title="Zoom in/out"></button>

                <!-- Preloader demo http://codepen.io/dimsemenov/pen/yyBWoR -->
                <!-- element will get class pswp__preloader - - active when preloader is running -->
                <div class="pswp__preloader">
                    <div class="pswp__preloader__icn">
                      <div class="pswp__preloader__cut">
                        <div class="pswp__preloader__donut"></div>
                      </div>
                    </div>
                </div>
            </div>

            <div class="pswp__share-modal pswp__share-modal--hidden pswp__single-tap">
                <div class="pswp__share-tooltip"></div>
            </div>

            <button class="pswp__button pswp__button--arrow--left" title="Previous (arrow left)">
            </button>

            <button class="pswp__button pswp__button--arrow--right" title="Next (arrow right)">
            </button>

            <div class="pswp__caption">
                <div class="pswp__caption__center"></div>
            </div>

        </div>

    </div>

</div>

Initialize

Put this part to the end of the dom because if no dom, js can’t find the target element. Or register this part as an event after dom be loaded.

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var pswpElement = document.querySelectorAll('.pswp')[0];

// build items array
var items = [
    {
        src: 'https://placekitten.com/600/400',
        w: 600,
        h: 400
    },
    {
        src: 'https://placekitten.com/1200/900',
        w: 1200,
        h: 900
    }
];

// define options (if needed)
var options = {
    // optionName: 'option value'
    // for example:
    index: 0 // start at first slide
};

// Initializes and opens PhotoSwipe
var gallery = new PhotoSwipe( pswpElement, PhotoSwipeUI_Default, items, options);
gallery.init();

Creating an Array of Slide Objects

Data structure

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var slides = [
    // slide 1
    {
        src: 'path/to/image1.jpg', // path to image
        w: 1024, // image width
        h: 768, // image height

        msrc: 'path/to/small-image.jpg', // small image placeholder,
                        // main (large) image loads on top of it,
                        // if you skip this parameter - grey rectangle will be displayed,
                        // try to define this property only when small image was loaded before

        title: 'Image Caption'  // used by Default PhotoSwipe UI
                                // if you skip it, there won't be any caption

        // You may add more properties here and use them.
        // For example, demo gallery uses "author" property, which is used in the caption.
        // author: 'John Doe'

    },

    // slide 2
    {
        src: 'path/to/image2.jpg',
        w: 600,
        h: 600

        // etc.
    }

    // etc.

];

DOM for build

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<div class="my-gallery" itemscope itemtype="http://schema.org/ImageGallery">

    <figure itemprop="associatedMedia" itemscope itemtype="http://schema.org/ImageObject">
        <a href="large-image.jpg" itemprop="contentUrl" data-size="600x400">
            <img src="small-image.jpg" itemprop="thumbnail" alt="Image description" />
        </a>
        <figcaption itemprop="caption description">Image caption</figcaption>
    </figure>

    <figure itemprop="associatedMedia" itemscope itemtype="http://schema.org/ImageObject">
        <a href="large-image.jpg" itemprop="contentUrl" data-size="600x400">
            <img src="small-image.jpg" itemprop="thumbnail" alt="Image description" />
        </a>
        <figcaption itemprop="caption description">Image caption</figcaption>
    </figure>


</div>

• Bind click event to links/thumbnails.
• After user clicked on on thumbnail, find its index.
• Create an array of slide objects from DOM elements – loop through all links
  and retrieve href attribute (large image url), data-size attribute (its size), src of thumbnail, and contents of caption.

JS implementation

pure Vanilla JS support IE8
The same in front, script execute need be after dom be loaded.

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// define a macro function
var initPhotoSwipeFromDOM = function(gallerySelector) {

    // parse slide data (url, title, size ...) from DOM elements
    // (children of gallerySelector)
    // Used to anaylsis the dom attributes
    var parseThumbnailElements = function(el) {
        var thumbElements = el.childNodes,
            numNodes = thumbElements.length,
            items = [],
            figureEl,
            linkEl,
            size,
            item;

        for(var i = 0; i < numNodes; i++) {

            figureEl = thumbElements[i]; // <figure> element

            // include only element nodes
            if(figureEl.nodeType !== 1) {
                continue;
            }

            linkEl = figureEl.children[0]; // <a> element

            size = linkEl.getAttribute('data-size').split('x');

            // create slide object
            item = {
                src: linkEl.getAttribute('href'),
                w: parseInt(size[0], 10),
                h: parseInt(size[1], 10)
            };



            if(figureEl.children.length > 1) {
                // <figcaption> content
                item.title = figureEl.children[1].innerHTML;
            }

            if(linkEl.children.length > 0) {
                // <img> thumbnail element, retrieving thumbnail url
                item.msrc = linkEl.children[0].getAttribute('src');
            }

            item.el = figureEl; // save link to element for getThumbBoundsFn
            items.push(item);
        }

        return items;
    };

    // find nearest parent element
    var closest = function closest(el, fn) {
        return el && ( fn(el) ? el : closest(el.parentNode, fn) );
    };

    // triggers when user clicks on thumbnail
    // register the click event
    var onThumbnailsClick = function(e) {
        e = e || window.event;
        e.preventDefault ? e.preventDefault() : e.returnValue = false;

        var eTarget = e.target || e.srcElement;

        // find root element of slide
        var clickedListItem = closest(eTarget, function(el) {
            return (el.tagName && el.tagName.toUpperCase() === 'FIGURE');
        });

        if(!clickedListItem) {
            return;
        }

        // find index of clicked item by looping through all child nodes
        // alternatively, you may define index via data- attribute
        var clickedGallery = clickedListItem.parentNode,
            childNodes = clickedListItem.parentNode.childNodes,
            numChildNodes = childNodes.length,
            nodeIndex = 0,
            index;

        for (var i = 0; i < numChildNodes; i++) {
            if(childNodes[i].nodeType !== 1) {
                continue;
            }

            if(childNodes[i] === clickedListItem) {
                index = nodeIndex;
                break;
            }
            nodeIndex++;
        }



        if(index >= 0) {
            // open PhotoSwipe if valid index found
            openPhotoSwipe( index, clickedGallery );
        }
        return false;
    };

    // parse picture index and gallery index from URL (#&pid=1&gid=2)
    var photoswipeParseHash = function() {
        var hash = window.location.hash.substring(1),
        params = {};

        if(hash.length < 5) {
            return params;
        }

        var vars = hash.split('&');
        for (var i = 0; i < vars.length; i++) {
            if(!vars[i]) {
                continue;
            }
            var pair = vars[i].split('=');  
            if(pair.length < 2) {
                continue;
            }           
            params[pair[0]] = pair[1];
        }

        if(params.gid) {
            params.gid = parseInt(params.gid, 10);
        }

        return params;
    };

    var openPhotoSwipe = function(index, galleryElement, disableAnimation, fromURL) {
        var pswpElement = document.querySelectorAll('.pswp')[0],
            gallery,
            options,
            items;

        items = parseThumbnailElements(galleryElement);

        // define options (if needed)
        options = {

            // define gallery index (for URL)
            galleryUID: galleryElement.getAttribute('data-pswp-uid'),

            getThumbBoundsFn: function(index) {
                // See Options -> getThumbBoundsFn section of documentation for more info
                var thumbnail = items[index].el.getElementsByTagName('img')[0], // find thumbnail
                    pageYScroll = window.pageYOffset || document.documentElement.scrollTop,
                    rect = thumbnail.getBoundingClientRect();

                return {x:rect.left, y:rect.top + pageYScroll, w:rect.width};
            }

        };

        // PhotoSwipe opened from URL
        if(fromURL) {
            if(options.galleryPIDs) {
                // parse real index when custom PIDs are used
                // http://photoswipe.com/documentation/faq.html#custom-pid-in-url
                for(var j = 0; j < items.length; j++) {
                    if(items[j].pid == index) {
                        options.index = j;
                        break;
                    }
                }
            } else {
                // in URL indexes start from 1
                options.index = parseInt(index, 10) - 1;
            }
        } else {
            options.index = parseInt(index, 10);
        }

        // exit if index not found
        if( isNaN(options.index) ) {
            return;
        }

        if(disableAnimation) {
            options.showAnimationDuration = 0;
        }

        // Pass data to PhotoSwipe and initialize it
        gallery = new PhotoSwipe( pswpElement, PhotoSwipeUI_Default, items, options);
        gallery.init();
    };

    // loop through all gallery elements and bind events
    var galleryElements = document.querySelectorAll( gallerySelector );

    for(var i = 0, l = galleryElements.length; i < l; i++) {
        galleryElements[i].setAttribute('data-pswp-uid', i+1);
        galleryElements[i].onclick = onThumbnailsClick;
    }

    // Parse URL and open gallery if it contains #&pid=3&gid=1
    var hashData = photoswipeParseHash();
    if(hashData.pid && hashData.gid) {
        openPhotoSwipe( hashData.pid ,  galleryElements[ hashData.gid - 1 ], true, true );
    }
};

// execute above function
initPhotoSwipeFromDOM('.my-gallery');

1. update

1

sudo apt-get update

2. nginx

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sudo apt-get install nginx

3. php

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sudo apt-get install php5-fpm
sudo apt-get install php-apc
sudo apt-get install php5-gd
sudo apt-get php-apc php5-common
sudo apt-get install php5-cli php5-cgi

php5-mysql when mysql need
php5-mcrypt when phpMyAdmin need

4. Nginx

• Static type file no log, one day expired

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  location ~* ^.+.(jpg|jpeg|gif|css|png|js|ico|xml)$ { access_log off; expires 1d; }

• The data type root directory could request

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  location / { # First attempt to serve request as file, then # as directory, then fall back to displaying a 404. #try_files $uri $uri/ =404; index index.html index.htm index.php default.html default.htm default.php; }

• Php type files’ deal process config

  1 2 3 4 5 6 7 8 9 10 11 12

  location ~ \.php$ { fastcgi_split_path_info ^(.+\.php)(/.+)$; # # NOTE: You should have "cgi.fix_pathinfo = 0;" in php.ini # # # With php5-cgi alone: # fastcgi_pass 127.0.0.1:9000; # # With php5-fpm: fastcgi_pass unix:/var/run/php5-fpm.sock; fastcgi_index index.php; fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name; include fastcgi_params; }

If php no this config, script may not work.
fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;

5. Restart & Test

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sudo /etc/init.d/nginx restart
sudo /etc/init.d/php5-fpm restart
sudo nginx restart
sudo php5-fpm restart

try request this script in browser
<?php phpinfo(); ?>

. Primary data type

• mapper interface

  1	User selectByPrimaryKey(Integer id);

• sql mapping

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  <select id="selectByPrimaryKey" resultMap="BaseResultMap" parameterType="java.lang.Integer" > select <include refid="Base_Column_List" /> from user where id = #{id,jdbcType=INTEGER} </select>

The id in this condition can be any name, it all represent the Integer parameter.

Discuss

if Integer argument need be judge use _parameter represent it in tag <if>

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<select id="selectByPrimaryKey" resultMap="BaseResultMap" parameterType="java.lang.Integer" >
  select
  <include refid="Base_Column_List" />
  from tb_user
  <if test="_parameter != 0">
  where id = #{id,jdbcType=INTEGER}
  </if>
</select>

Object data type

• mapper interface

  1	int insert(User user);

• sql mapping

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  <insert id="insert" parameterType="User" useGeneratedKeys="true" keyProperty="id"> insert into tb_user (name) values (#{name,jdbcType=CHAR})

• The name in value must be the User object’s property name

• If <if> tag want to judge whether user is null, _parameter variable need be used. like above discuss content.

Map data type

• mapper interface

  1	int updateByExample(@Param("user") User user, @Param("condition") Condition condition);

• sql mapping

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  <update id="updateByCondition" parameterType="map" > update tb_user set id = #{user.id,jdbcType=INTEGER}, ... <if test="condition != null" > <include refid="Update_By_Condition_Where_Clause" /> </if> <if test="_parameter != null" > <include refid="Update_By_Default_Where_Clause" /> </if>

• use #{keyname} to reference target

• @Param(“…”) is alias manule point the map key name
• Multi argument will auto box into a map

Collection data type

You can pass a List instance or an Array to MyBatis as a parameter object. When you do, MyBatis will automatically wrap it in a Map, and key it by name. List instances will be keyed to the name “list” and array instances will be keyed to the name “array”.

• mapper interface

  1	List<User> selectUserInList(List<Interger> ids);

• sql mapping

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  <select id="selectUserInList" resultType="User"> select * from user where id in <foreach item="item" index="index" collection="list" open="(" separator="," close=")"> #{item} </foreach> </select>

Object’s collection

• mapper interface

  1	List<User> selectByCondition(Condition condition)

• sql mapping

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  <where > <foreach collection="threshold" item="limit" separator="or" > <if test="limit.value > 10" >

• threshold is a collection property in condition

• limit represent the item in collection

link:
MyBatis input argument and parameterType

Urllib

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import urllib2

response = urllib2.urlopen("http://www.linchenguang.com")
print response.read()

analysis

urlopen(url)
urlopen(url, data, timeout)
urlopen(Request)

• Is this a multi status in python
• timeout in default is socket._GLOBAL_DEFAULT_TIMEOUT
• data in default is null

request = urllib2.Request("http://www.linchenguang.com")

Get

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import urllib
import urllib2

values={}
values['username'] = "admin"
values['password'] = "admin"
#values = {"username":"admin","password":"admin"}
data = urllib.urlencode(values)
url = "http://passport.csdn.net/account/login"
geturl = url + "?"+data
request = urllib2.Request(geturl)
response = urllib2.urlopen(request)
print response.read()

• data compatible with json, array style is similar with js
• data need urlencode prevent unreserved characters ambiguity
• data parameters connect with url with ?

Post

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import urllib
import urllib2

values = {"username":"admin","password":"admin"}
data = urllib.urlencode(values)
url = "https://passport.csdn.net/account/login"
request = urllib2.Request(url,data)
response = urllib2.urlopen(request)
print response.read()

• data be referenced in Request method as a parameter
• post has two phase transport progress