RTB业务知识之2-Impression概念和关键属性

一、定义-impression

　　This object describes an ad placement or impression being auctioned. A single bid request can include multiple Imp objects, a use case for which might be an exchange that supports selling all ad positions on a given page. Each Imp object has a required ID so that bids can reference them individually.
The presence of Banner, Video, and/or Native objects subordinate to the Imp object indicates the type of impression being offered. The publisher can choose one such type which is the typical case or mix them at their discretion. However, any given bid for the impression must conform to one of the offered types.
二、翻译

　　impression在百度百科上被翻译为印象，定义为：放置广告图像的网页每一次显示，就是一次印象。

　Impression描述一次广告投放或者被拍卖的印象。一个竞价请求包括多个Imp对象，一个典型的应用场景是：一次交换支持销售一个页面所有的广告位。每一个印象对象包含一个请求ID，因此竞价平台可以单独引用他们。

三、属性

Attribute	Type	Description
id	string; required	A unique identifier for this impression within the context of the bid request (typically, starts with 1 and increments.
banner	object	A Banner object (Section 3.2.3); required if this impression is offered as a banner ad opportunity.
video	object	A Video object (Section 3.2.4); required if this impression is offered as a video ad opportunity.
native	object	A Native object (Section 3.2.5); required if this impression is offered as a native ad opportunity.
displaymanager	string	Name of ad mediation partner, SDK technology, or player responsible for rendering ad (typically video or mobile). Used by some ad servers to customize ad code by partner. Recommended for video and/or apps.
displaymanagerver	string	Version of ad mediation partner, SDK technology, or player responsible for rendering ad (typically video or mobile). Used by some ad servers to customize ad code by partner. Recommended for video and/or apps.
instl	integer; default 0	1 = the ad is interstitial or full screen, 0 = not interstitial.
tagid	string	Identifier for specific ad placement or ad tag that was used to initiate the auction. This can be useful for debugging of any issues, or for optimization by the buyer.
bidfloor	float; default 0	Minimum bid for this impression expressed in CPM.
bidfloorcur	string; default “USD”	Currency specified using ISO-4217 alpha codes. This may be different from bid currency returned by bidder if this is allowed by the exchange.
secure	integer	Flag to indicate if the impression requires secure HTTPS URL creative assets and markup, where 0 = non-secure, 1 = secure. If omitted, the secure state is unknown, but non-secure HTTP support can be assumed.
iframebuster	string array	Array of exchange-specific names of supported iframe busters.
pmp	object	A Pmp object (Section 3.2.17) containing any private
ext	object	Placeholder for exchange-specific extensions to OpenRTB